Time Split Tracker (Windows version)
A downloadable TST for Windows
This is the Windows version of Time Split Tracker (which also works on WINE), which keeps track of your splits (there is a timer mode if you want a timer without splits), and as many comparisons to your splits as you want, and offers a wealth of information to make it easy to track the performance of the current run. This also keeps track of best splits, and some statistical information about your runs.
Please report bugs, issues or feature requests in the forum here or in the Mac version forum since I check both.
The Mac OS X version of Time Split Tracker (which is based on this version and shares the same engine) can be found here: