Cradle of Rome is a great game a bit similar to Bejewelled.
There are various versions of it on the net. I got so hooked I tracked down and even paid for the full version which has 100 levels... was worth every penny too!
I love those games. You might like another one along similar lines called Puzzle Hero. It has RPG elements and is pretty addictive. Couldn't find a browser version though. Big Kahuna Reef is another one.