Rock Rats includes quite a few hidden achievements. Some you'll naturally stumble across from playing, but others are a little harder to uncover. Here are some hints for prospective easter egg hunters.
There are several special scores that will give you an achievement if you reach them and don't immediately go over. Most of the scores are numbers associated with science fiction works.
Rock Rats was inspired by a game that appeared in '79.
If stuck in the past, how might you get back to the future?
When you've accomplished almost everything that the game offers, perhaps you should think back to the time when you first joined as a new recruit.
The main menu and tutorial each hold secrets. And developers can be sneaky.
If you're stuck and unable to find the last few achievements (and are not inclined to read the source code), then here are all the hidden achievements you can earn.