web cam---advice

Hi---trying to shop for a web cam as a gift and I know nothing about them. I'll read mag reviews and such about 'em---but wanted to know if anyone here had any words of advice..
 
Have you had/used one?
 
What did you like best about it? least?
 
What would you say to look for when buying one? is there something you would avoid?
 
Most important feature? least important?
 
Thanks!