I shoot with a canon s3 is, that and its newer sibling can be found in the range you are looking for.
Its a great super zoom with fully manual features as well as highly hackable with chdk for custom scripts, forced operations modes, killer electronic shutter speeds, and nice overlay grds. It has an adjustable fold out viewfinder for great shoot from the hip or above your head views.
With a simple adapter you can add on filters and lenses. the filters are cheap as dirt on sites like dealextreme.
I carry a Coated UV, kenko circular polarizer, hoya linear polarizer, and a cheap massa IR filter. With the 2 polarizers on top of one anohter you can use them as varialbe neutral density filters, they work well until the near black end where there is a blue shift. but great for space saving and speed.
Also pick up a rubber eye cup for this camera it greatly helps the evf in all situations, had on ebay cheaply.
I made this whole set for under 250 bucks as i got the camera really cheap. check out the flikr groups for this camera, you will be impressed.