Most of ICPC veterans I know joined companies like Google, Facebook, Yandex or some younger tech startups (1, 2, 3) or stayed at university, getting their scientific degrees and training some high school / university students in the process. That's all quite boring. I recently found out about some unusual careers of former olympians. By "unusual" I mean something like this:
Nikolai Durov — won ICPCs of 2000 & 2001 and also performed really well at some IOIs and IMOs. He co-founded VK and Telegram. (I don't think I really needed to introduce him)
Leonid Volkov — 14th place (bronze) at ICPC '01. He went into politics and now he is the chief of staff of Alexei Navalny's campaign (he is quite a trending oppositioner in Russia)
Just for fun, what other examples do you know of?