Extended profiles

It'd make a good plugin -- maybe an extra table with name-value pairs, like:

User ID	Property Value 1	Favorite language PHP 2	Favorite language Python 1	Experience level expert 2	Experience level beginner

Actually, this is probably something that could go into core...

It might be a good idea to extend it to GROUPS and NOTICES. We could then use NOTICES like EVENTS, RATINGS, REVIEWS, ETC and GROUPS for DEPARTMENTS, ORGANIZATIONS, COMPANIES, ETC...