The interoperable wonder, Trillian, introduces its commercial Pro version. We think it's worth the dough.

Our favourite instant messenger (IM) just got better. Trillian Pro now comes with a price tag of US$25 (AU$46). This is unlike most other IMs out there, but it's worth every penny to power IM users who depend on instant messaging to stay in touch and have buddies on AIM, ICQ, MSN, or Yahoo. Trillian Pro is still rough in places--some features are half-baked, including its support for Yahoo's Webcam--but it packs in scores of new tools and better tech support. Casual IMers should stick with the free Trillian 0.74, but if you rely on instant messaging, Pro is the way to go.

PayPal required
Buying Trillian Pro is the hardest task you'll encounter with this app--you can pay only via PayPal for now. Trillian Pro installs in just a few moments, and if you're upgrading from an earlier free edition, the program will retain all your IM accounts and contacts. The new version sports a more colorful interface, but like the free version, it's still skinnable , meaning you can download and install various new looks and themes.

Impressively, Trillian Pro chewed up just 5MB of memory on our test XP Home Edition system--only about one megabyte more than the regular version. By comparison, AIM uses about the same amount, while the full version of ICQ uses about 6MB.

Pay for an IM client?
Trillian Pro includes scads of enhancements and features--more than enough to justify the US$25. Our favorites include the new Metacontacts, an ubercontact list that represents all the IM services your correspondents use. If Kathy uses MSN, ICQ, Yahoo, and AOL, for instance, you can see on the Metacontacts that she's online, and on which service or services. Trillian Pro also offers a tool called Word Matching. You can list and define certain words; then, when one appears in a message, Trillian can highlight it for emphasis, automatically insert a replacement (great for deciphering wacko nicknames that friends sometimes use), or even pop up an alert.

But Trillian Pro's sweetest enticement is its new plug-in feature. To give Trillian more functionality, you can download small, free add-ons that provide a variety of services, including notifying you of new mail in your POP3 accounts, grabbing headlines from news feeds, and even integrating a Winamp toolbar for fast access to tunes. So far, Trillian offers only nine plug-ins (check them out on Cerulean Studios site), but we're eagerly awaiting more.

Security, always a concern in instant messengers, isn't much better in Trillian Pro than in its free sister software, but the service adds 128-bit encrypted messaging when you chat with other Trillian users (free or Pro) over AOL and ICQ. As with previous versions, Trillian still has trouble both sending and receiving files across a firewall, so you may have to manually tweak your router or software firewall to get Trillian to properly transfer files. Corporate users, unfortunately, might never succeed.

E-mail support now included
What else does your US$25 buy you? Support. Trillian Pro comes with a year's worth of updates and gives you access to e-mail tech support as well as the excellent user-to-user message forums. The online help is a bit spotty and not sufficiently detailed, but the message boards provide thorough answers nearly every time. To test the new e-mail support for paying customers, we asked for help with one of the new plug-ins and got an on-the-mark answer within 12 hours.

For anyone who lives with instant messaging all the day long, Trillian Pro's US$25 sticker price is a bargain. It has a few kinks to work out, but for connecting to pals on more than one service, Trillian is the best. Casual IMers, though, will find plenty of satisfaction with the still-free Trillian 0.74.

Cerulean Studios Trillian Pro
Company: Cerulean Studios
Price: US$25

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