London's bike hire scheme - Barclays bike hire - have a website that gives real-time information on the availability of bikes/spaces at the different stations all across London. The first thing that struck me was the number of hire stations and bicycles scattered around central London. Quite incredible.
It is a little difficult to use at first but once you get the hang of it, it provides interesting information on the use of the scheme. If you go to the grid view - press G and the map morphs into a grid - you can zoom into each station and see what the use has been over the last 24 hours and how many bikes are there right now.
It is interesting to see how many stations have very strong fluctuations in use (like Hyde Park corner below) while others see limited use (like Knightsbridge). The timing in the peaks is also interesting and would appear to show the main direction in flows.
There is a wealth of information on how people move in the city that these bikeshare schemes can gather. I am sure there are a few doctoral theses that you could do on transport planning in inner cities using the information.
Brisbane's CityCycle scheme and Melbourne's Bike share scheme have real time maps (CityCycle map here, Melbourne map here) where you can get information on the number of bicycles or spaces available at any station. They don't give a history of use though so it is impossible to see a history of usage.
Interestingly the information in the CityCycle web site has a field 'credit cards accepted'. All the stations currently indicate that no credit cards are accepted, but this possibly points to this being a feature that can be added.