Do you have tons of RAM in your system, with a lot of it free, yet reach a limit where you can't open any more applications, or the toolbars and menus disappear? Here's why and how to fix it:
http://www.rojakpot.com/default.aspx?location=3&var1=238&var2=0
I've wondered about this for years (as I typically have dozens of applications open), and now I know how to take care of the problem.