A while back Otime posted a message about wide angle convertors and the DMC-FZ1. I've been sitting on this link for a while :
http://kazutoku.maxs.jp/Zoom_Club/CL/index.htm
I think it shows fairly good performance with Olympus WCON-08 (to get 28mm equivalent). The slightly wider "Hakuba" lens shows a bit more distortion and edge softness. Not too bad though.
I've heard of a few convertors which work well Canon G2/G3 which are also said to work well with the DMC-FZ1. So here's a couple of pages on converters and the Canons; first shows piccies of converters (of course the WCON-08 is big....), second has links to show how they perform with Canon G3 :
http://kazutoku.cside21.com/G1andG2/telewide_eng.htm
http://kazutoku.cside.com/G3CON_eng.htm