California Governor Arnold Schwarzenegger and Billy Bob Thornton made surprise appearances on pal Jay Leno's The Tonight Show on Monday (26SEP05) - just to add their signatures to a charity Harley Davidson.

Funnyman Leno is hoping to raise $1 million (GBP555,500) for the Hurricane Katrina relief effort by auctioning off the motorbike on eBay.

Schwarzenegger is hopeful his friend will reach his target, because the last signature-strewn Harley Leno auctioned off - for last Christmas' (04) tsunami relief effort went under the hammer for $800,000 (GBP444,400).

And the action man-turned-politician admitted it was a pleasure to sign something he wouldn't be castigated for, joking, "At least I can sign something that my opponents won't criticise."

The yellow motorbike also features the signatures of Jodie Foster, Denzel Washington, Ben Affleck, Joaquin Phoenix and Heather Locklear