Maybe I just want to have multiple applications running in parallel. At the work I may have 10 Visual Studio solutions open, three remote connections via RDP, stupid Lotus Notes (sh*t IBM software but unfortunately it is our email solution), few browser instances and some utils including TortoiseSVN, possibly checking out multiple repositories at once. None of them are particularly demanding but with all that stuff together I would appreciate having more RAM than just 4 GB.
+1
I can't get away with less than 8 gigs on my work machine.