I'm surprised at people slating C&C3 - great game IMO. Ive always loved the Tiberian universe and this was, although not everything I was hoping for, a good return to the roots of the series and a fun game in its own right.
Worst 3 purchases I've made:
1 - Global Power - dear God, why did I buy this awful spreadsheet collection? So, so awful in every possible way.
2 - Master of Orion 3 - much the same as #1. Awful collection of numbers and totally without a soul or any sense of fun. GalCiv shows how these games should be done.
3 - Darkstar One - my old pc couldn't run it, and my new one is running 64-bit Vista - DS1 won't run on 64 bit operating systems and they refused to patch it to make it do so! Paid about £25 and have never played it.