My son loves riding the S-Bahn, and I'd like to find him a toy S-Bahn train. Just something cheap, nothing fancy. However, I can't seem to find one anywhere. At the BVG place at Bahnhof Zoo they had buses and streetcars, but no S-Bahn. I've checked the toy sections at Woolworth and Karstadt, and a gazillion different Berlin souvenir stores, all to no avail. The only ones I've found are not for kids, but for toy train hobbyists (and, thus, are very expensive). Anyone have any ideas?