There are two European startups trying to disrupt the rail booking space by making the experience quick, easy and effective. Capitaine Train is one, based in Paris, and Loco2 based in London is the other.

Both offer tickets from a fair variety of European train operators to book online - France, Germany, Spain, UK, Eurostar etc. It's not all operators, but they're both working hard to add more countries. (I know many of the girls and guys at Loco2, a friend knows the Capitaine Train crowd, both companies are made up of smart, passionate people).

The biggest difference is that Capitaine Train sells tickets priced+billed in Euros, while Loco2 sells in GBP (£). Depending on the card used, the FX/fees savings may swing you one way or the other! Prices should be about the same between the two, modulo exchange rate movements, though there's the very odd case where the SNCF France and UK booking systems see different availability of cheap tickets so the prices will be different between the two. (CT talk to SNCF in France, Loco2 in the UK, and they're almost always but not always the same...). CT also offer a few more advanced things like certain loyalty cards, but Loco2 are set to add that soonish. Otherwise, if the currency doesn't swing it for you, try both and pick the UI you prefer!

Also, until the 31st of January, Capitaine Train are offering a signup bonus. If you sign up with This Capitaine Train Signup Link, you'll get €5 off your first booking. Sadly that bonus then goes away.

I've used both Loco2 and Capitaine Train, and they're both good