Just make a 2nd (or even 3rd) row... or try putting the taskbar on the left or right side.
Sometimes I have over 75 programs left open and this is never a problem. Of course I have the screen at work set to 2560x1536 and 2 rows on the taskbar.
If you are using Win2K which doesn't normally group things like XP, ObjectBar will let you change that and helps immensely.