I think CrunchBase is a really nice resource. For those of us bemused by the silly throwing around of money that is going on at present, this database is a nice way to search. So I can easily look up any company (eg Jaiku) and find out what hell people are attracted to it for, and even some financial data if any is available (eg here's a new company you may not have heard of :-). Michael Arrington gives a good overview of the aim behind the database. I'm hoping in time there will be easy web service or API enabled access to the data.