While viruses are not  a major risk for Mac users, it’s still prudent to have an anti-virus application installed on your Mac. Sophos offers a free Macintosh anti-virus application for use on home computers. Give it a try.

Why would you need an anti-virus application on your Mac? I can think of a couple of reasons.

1. While there aren’t many Mac viruses, there are some Mac OS X Trojan Horse viruses. I still occasionally come across some Word Macro viruses also, which were common on Macs in the late 1990s.

2. You might receive an email attachment which contains a PC virus. While this virus can’t do any harm to your Mac, would you want to pass this virus on to a friend or family member who has a PC? Sure, that person should have their own anti-virus protection, but it still doesn’t look good that you’re passing on viruses.

If you have business computers you can also use Sophos, but you’d have to buy an initial license. Sophos requires the purchase of a minimum of 3 licenses for about $34 per license. Volume discounts kick in at 10 licenses.

Check out Sophos Anti-Virus. It’s free for home users. It can detect if your Mac already has any infected files and can prevent you from getting infected in the future.

What is iCloud? iCloud is a cloud computing service offered by Apple since October 2011. In a recent Tech Tip we got a brief overview of cloud computing. Now let’s look specifically at Apple’s iCloud. There are a lot of answers that one can give to the question, What is iCloud?

iCloud is a free data synchronization service that connects your Mac (or PC), iPhone and iPad. While the core iCloud services are free, there are optional features which cost money. Apple describes iCloud this way. iCloud stores your music, photos, documents, and more and wirelessly pushes them to all your devices. Automatic, effortless, and seamless — it just works. You can watch Apple’s video demonstrating iCloud.

iCloud is the successor to Apple’s MobileMe service. iCloud is really the fourth iteration of Apple’s online service. Wikipedia’s article about iCloud reviews this history. MobileMe had a shaky reputation in terms of reliability. When it first launched there were many incidents of slow performance and lost data. Personally, I’ve seen MobileMe data get corrupted that caused syncing to stop working. Apple redesigned and built iCloud from the ground up. It hopes to impress us with its rock-solid reliability. So far, I’ve been pretty pleased but I feel it’s a touch early to pronounce my final judgement.

According to Tim Cook, Apple’s CEO, iCloud is more than a product. It’s a strategy for Apple for the coming decade. Cook implies that iCloud will grow over the coming decade to offer more and more services.

iCloud offers an array of services which I won’t list here. Many others have already covered these services thoroughly. Here are links to two such articles I think do a particularly good job of describing iCloud’s current services. David Pogue’s blog post about iCloud and Gotta Be Mobile’s blog post about iCloud.

There are a number of easy ways to convert an .mp3 song file to a ringtone for your iPhone. I typically use Garageband since the method is quick and easy. I realize that not everybody owns Garageband, so I’m pleased to share this other free method. Compared to using GarageBand there are more steps, but it’s not difficult to do.

Important: This process doesn’t work for copyright-protected songs (.mp4) purchased from the iTunes store.

• Open iTunes, go to the iTunes menu and select Preferences.
• Click on the General button, then click the Import Settings button.
• From the pick-list next to “Import Using” select AAC Encoder. Click the OK button. Click the OK button a second time to exit out of Preferences.
• Play the .mp3 song file you want to convert to identify the 20-30 section of the song you’d like to use for the ringtone. Specifically, you’ll need to write down the start and end time of your desired section. You can do this by watching the timer that iTunes displays near the top of its window.
• Click once on the mp3 song file. Go to the File menu and select Get Info.
• Click on the Options button so you can enter the Start and Stop times to set the 20-30 section that you want to become your ringtone.
• Go to the Advanced menu and select Create AAC version. [Update March 2013: In iTunes 11, instead of using the Advanced menu, right-click or  control-click the song and choose Create AAC Version from there.] This will cause a duplicate copy of the song file to be created. This duplicate copy will only be the length you selected when you set the Start and Stop times.
• Before you forget, return to the original mp3 song file and clear the Start and Stop times. You don’t need to re-enter the original times. I simply leave these fields blank and iTunes automatically knows to play the entire song.
• Click on the newly created AAC song file to select it.
• Go to the File menu and select Reveal in Finder. It may be listed as Show in Finder instead. This will open a Finder window showing you this AAC song file. Leave this window open. We’ll return to it in just a minute.
• Go to iTunes and make sure your AAC song file is selected.
• Go to the Edit menu and select Delete.
• You may be asked if you’re sure you want to remove this file from your iTunes Library. You’re sure, so click the Remove button.
• Next, you’ll be asked, “Do you want to move the selected song to the Trash or keep it in the iTunes Media folder?” Click the Keep File button.
• Return to the Finder window that you left open. You’ll see the AAC version of the song file. You can identify it since its filename ends with .m4a file.
• Change .m4a to .m4r
• Drag this .m4r file onto the iTunes on the Dock. This will import this .m4r file into iTunes and it’ll show up in the ringtones section.
• Sync your iPhone and make sure that you’ve selected to sync all Ringtones. This will add the ringtone to your iPhone. Then you can assign it to a particular person listed in Contacts.

Zamzar, an online file conversion service, is an easy way to save a copy of a YouTube video on your Mac. To do this you enter the YouTube video’s address at Zamzar’s web site and it will convert the YouTube video into a file type which you choose, then send you an email containing a link to download the  converted file.

Zamzar is actually a very versatile file conversion service. I’ve used it to convert Microsoft Visio drawings, Microsoft Works files and Microsoft Publisher files. To read Zamzar’s huge list of supported file types visit this web page.  Zamzar offers several levels of service. Their free accounts are ad-supported. Free accounts are limited to processing upto 20 files per day which add up to not more than 500 MB. Paid accounts let you overcome these limitations as well as offering additional features.

Update: Here’s another possible option. Jaksta is a commercial application which claims to let you save a copy of any audio or video file that you stream in your web browser.