HH2B_4EVER
HH2B & HH3A non-official router firmware
Home Hub 2 Type B Non-official all singing and dancing improved firmware
Now Plus Home Hub 3 Type A!
Note:
Although this is a good source of how some of it was done; please whiz over to http://openwrt.ebilan.co.uk/ for up to date info...
V2A, V2B and V3A are now supported in OpenWRT.