Arietta G25 is a small and low-cost multi-chip module that integrates a 400MHz Atmel AT91SAM9G25 ARM9 CPU, 128MB of DDR2 RAM, a microSD card slot, a USB Device port, space for adding a WiFi module, and a 2×20-pin extension header with 2.54mm pitch.
This makes a great embedded Linux module for your next project. A bootable Debian Linux build for this module is available for download which you can install on a microSD card.
You also can get a 256MB version of the Arietta.