I asked the same question in the misc accesories section, and got no reply. That was more than 5 days ago. I read in a different thread (searched for "bag") and people suggested the Nova 2 (I think) for the FZ5 or FZ20.
A local online digicam dealer suggests the LowePro D-Res 40 AW for the S2. I haven't yet found one in a shop, so cant tell you how well it is suited.
I looked at the LowePro Edit 110 in a store, and is a very nice fit for the S2. Maybe a little to small for te charger though.The cheapest one I found though (when converting from Rands back to $) was $37. Found an edit 120 at a different store for $16.50, but they had no stock, so its just that other store thats too expensive.