UK: Jailbreak/Groove USB friendly hub in Poundland!
After finding that nearly all the hubs I've had plugged into my PS3 needed to be unplugged to have Jailbreak, I stumbled across this one at Poundland in the UK.
For one pound, I thought I'd give it a go, and it turns out I can turn my PS3 on into Jailbreak mode with the hub. Plus, it also works with the Jailbreak device actually in the hub instead of the USB socket on the PS3.
The downside is you still can't have anything else plugged into the hub apart from the Jailbreak otherwise it doesn't work, but it's a step up from every other hub I tried which stopped Jailbreak working when I'd got the hub plugged into one PS3 port and Jailbreak/groove into another.