Hi
Indeed SUMPRODUCT is like SUMIF on steroids.
In Excel 2007 Microsoft has created 3 new functions SUMIFS, COUNTIFS and AVERAGEIFS that can do a lot of what SUMPRODUCT can do but not everything.
During a recent visit to their campus in Redmond I showed them what I do with SUMPRODUCT and they were flabergasted. Useless to say that the creators of the new functionsdidn't become my friends.
SUMPRODUCT is at the center of my practiceas consultant and mentor. SUMPRODUCT empowers regular users and reduces substantially the programming needs.
If 5% of Excel users knew about SUMPRODUCT it would change the world of reporting and a lot of small businesses would not need to buy expensive, complex and limited reporting programs.
See an introduction on my website.