For me, it was perhaps simple-scan, a very simple and efficient GUI to scan documents. I used it with my Brother printer / scanner and it works like a charm. Especially since I do not scan stuff often, so a program with more complex UI would have the effect that I forget how to use it until the next time.
Tux racer was neat.
There was also a weird space game that started with a Q. I never progressed and it gave me existential crisis as it felt like nothing was out there. I’d get lost in space every time.