Asia - Sri Lanka Beaches

I'm considering doing a short trip (relatively) to Sri Lanka around Christmas time. Just wanted to know if anyone had any suggestions on what beaches they most enjoyed. Prefer something not too developed and decent facilities, would rather not do the resort thing.

The potential to go scuba diving would also be nice (should be PADI certified by then)...

Any ideas would be most appreciated.

Mirissa (http://maps.google.com/maps?f=q&source=s_q&hl=en&geocode=&q=mirissa+sri+lanka&sll=37.901428,-122.262951&sspn=0.008398,0.013089&ie=UTF8&ll=5.943707,80.459318&spn=0.010586,0.013089&z=16). Here's (http://www.mirissa.com/getthere.htm) a wry advice page on how to get there and return. The higher level pages have additional information.