I have added a section about overclocking to the PB44 wiki page that I created a few weeks ago. I am running mine at 720 MHz (default 680) and with 66 MHz PCI bus (default 33). I also included information on how to push it to 760 or 800 MHz, including increasing CAS latency on the DDR to 3 (default 2.5) for increased RAM stability. The 760/800 configs are not stable on my router, though I have two more PB44's I could test with.
I also added information about some GPIO mods, including making use of the LED's on the RS232-TTL converter board and adding I2C devices.
I had also previously added information on making use of some LED's that are not accessible in the default images, such as the "PWR" LED, and the second LED (other half of the dual LED) for each Mini-PCI slot. I use this information to build support for these LED's into my own images.
I hope this is interesting to some PB44 users, and even to users of other routers using AR7161/AR71XX CPU. If you try overclocking your PB44, post the results here.
If anyone else has done, or thought about doing, any interesting hacks to/with their PB44, post details here.