After swapping my old comp's 192MB RAM with the recently borrowed one's 128MB, I don't think I'll ever need another new machine for a long time to come ! :)
Apps that I run at any point of time on the home comp are (also refer to my must have software list here)
Apps that sit on the tray include
1. Spybot S&D
2. Zonealarm Personal Firewall
3. AVG Antivirus
4. Google Desktop Search.
Yahoo Messenger is an occasional add on.
Let's see how long this "new" config helps me to stay in my senses. Maybe I'll try upgrading RAM much more - say to 512MB or 1GB if necessary !! That should help me to keep this thing going for a long time.