Over at CNXSoft, a user called omgfire has composed a list of 39 low cost Linux development boards. Dominated by ARM, two (rather expensive) VIA boards are a part of the list.
Personally, I have access to PandaBoard, BeagleBoard, Trim-Slice and soon a RaspberryPi (I have a tracking number). Which have you tried working with? What distros are suitable for which board?