rollback rx (nuke yr computer and reboot to previous snapshot)
everything (quick as you type file search, similar to locate32)
quotetracker (if you daytrade/ invest in stock, you'll love this.....tdameritrade clients get free registration)
vmware (run sandboxie inside this to prevent virus hopping from downloads to main rig)
presto! linux (quick boot ~10seconds linux, even after trial period, good to have it around prior bedtime for 10minute surfing
instead of "oh look the sun is up" pre-bedtime surfing)