Spaceplan is a fantastic free idle clicker for your web browser from Jake Hollands. It’s similar in style to the original popular idle clicker, Orteil’s Cookie Clicker. Cookie Clicker is probably inspired by Progress Quest, which involved no clicking and instead was more of a parody of your classic online MMORPG.
These are games where numbers increase in response to some minimal set of actions on your part, usually while you’re not paying much attention to it, and some small amount of strategy to decide what upgrades you would like to help make which numbers increase quicker. That strategy is vanishingly small in Spaceplan because Spaceplan actually has a story and an ending. Which is very unusual for this type of game. You can restart with the same equipment and keep going, but the payoff at the end is very much worth your time.
Prefixing things with the word space is still cool, you should give Spaceplan a shot.