i have a philips ToUcam ii pcvc820k
it runs with the omnivision (ov511) driver
though as ov 518 camera it needs a decompression module, which is no standard in the distribution kernel. driver versions with decompressor can be downloaded at it's author's site:
http://alpha.dyndns.org/ov511/
the ov511 driver gives access to many common usb camera's. though i found it quite hard to find camera's from the list 'supported' in the shops. be precise and careful: webcams can be tricky as the box reveals little on the contents and nothing on the actual chip used in the cam. it can vary within the same brand and camera type.