My newest project is a way to race other people with bike trainers on the internet. My goal is to have this as inexpensive as possible - hopefully under $10 or so. I'm not as concerned about fancy graphics or racing courses as much as "am I winning?", and having a reasonable price. So far, I have a simple C program that reads the joystick and calculates the time and distance traveled.
Distance (km) = 0.177 Time = 0:00:29.332 km/h = 54.025
Distance (km) = 0.179 Time = 0:00:29.452 km/h = 64.830
Distance (km) = 0.182 Time = 0:00:29.676 km/h = 34.730
Distance (km) = 0.184 Time = 0:00:29.876 km/h = 38.898
Distance (km) = 0.186 Time = 0:00:30.084 km/h = 37.402
Distance (km) = 0.188 Time = 0:00:30.284 km/h = 38.898
Distance (km) = 0.190 Time = 0:00:30.508 km/h = 34.730
Not too fancy so far, but data collection seems pretty good.