Jo -

There are folding bikes out there, you know, that you can take with you on the train. Ummmm, <smoke pouring out of ears> Brompton(?) is one of the brands. There are others...

Rumor has it that there are (were) folding bike races in London(?) I actually saw a bit of a video on it once. The guys rushed off a train, unfolded their bikes and biked to the finish line. The unfolding stage was a hoot.

It might be worth some research, esp. if The Powers That Be don't install bike lockers in you station. The way gas prices are, a folder would pay for itself in a hurry. And just think of the bikejournal miles.