I'll bite, because I like to know what everyone else is running...
Firefox, loaded with SEO extensions/plugins
Safari, tabs open to a variety of sites providing free proxies
Chrome, tabs open to Google Docs, Gmail, Analytics, Keyword Tool and Search Insights
I surf using IE because all of my other browsers are bogged down with extensions and I never liked Opera.
Raven Tools
Traffic Travis (still have it, but between Raven Tools, Firefox's extensions and the tabs I have set up in Chrome, I really don't need it but I'm used to it)
SEnukeX (re-learning after a long hiatus away from it.)
Scrapebox (really need to learn to use it better)
Wordpress (OK, . Bite me.)
Drupal (just started learning it, and no it's not on my PC but the Kindle app and ebooks for it are.)
Powerpoint/Excel (MS Office)
Camstudio
Microsoft Expression Web 4 (Got it for free since my "dayjob" is at a University Hospital)
Norton Antivirus (Got it for free, see above)
Filezilla (Been using it for years, no reason to switch)
Relakks (Encrypted VPN Tunnel with a good reputation)
Recently downloaded Eclipse to learn Java Programming for Android Apps
I'm about to acquire two used, 2-year-old laptops from friends who have switched to Macs, so I am planning to move SEnuke and Scrapebox to dedicated PC's that just have my tweaked Firefox and Chrome browsers installed on them - nothing else (well, besides Norton and Relakks).
Other apps not related to IM:
revo uninstaller
ccleaner
Smart Defrag
miro
AnVir Task Manager Free
Belarc Advisor
Edit: I forgot a few: uTorrent, HTTrack Website Copier, 7zip, Virtual PC, Splashtop Remote (lets me access my home PC from my Android phone), Skype, and I just downloaded Visual Studio 10 just for the heck of it (It's a $500+ application that I'll probably never use - MS's Dreamspark.c0m site is awesome!). My PC's are so loaded with so many tools that I'm seriously thinking of getting a netbook just for presentations and MS Office, and running it without anything IM related on it. (I can access Raven Tools for a client, if I need to.)