The D-link
DAP-1350 is a small (..pocket sized) AP/router with a Ralink RT3052F SoC, it has a
MIPS32 24KEc core clocked at 384MHz. The
RT3052 has a 802.11 b/g/n radio as well as an Ethernet switch, It also supports USB OTG (..on the go) which is register compatible with EHCI.
The DAP has 32MB of RAM, 8MB of flash, 1 physical Ethernet port, and a USB port.
There is source for u-boot, the Linux kernel, and FreeBSD (..kernel bits are upstream). The RT3052 is technically supported in OpenWrt, but not the DAP-1350 platform.
It's apparently common, but the flash memory is partitioned, this means you have a chance of restoring the firmware assuming you only write where you're supposed to.. restore can be done using TFTP, serial UART (..soldering required), and HTTP (..this is neat, u-boot + uIP + a tiny HTTP server with an HTML form).
Developing for this platform is possible, but information is kind of disorganized.. same goes for a lot of non-x86 platforms. I have found datasheets for the SoC, which covers most of the hardware, but redistribution is an issue.
It cost me less than $60 at Walmart, and I was only looking for an AP, not a new toy.