I still regret buying Terraria for the 360. Hated that controller. Keyboard is much better. Depending on HOW crappy your laptop is, I'm guessing you might not want any graphics at all. If you're looking for something browser based, you should try Initium. I started playing Initium two days ago after someone mentioned it on reddit. Its like an MMO/Roguelike/MUD completely browser based and mobile friendly. I've logged like 20 hours so far. It's ridiculous. You'll thank me later.

Another browser based game I've been playing for like 5 years is Urban Dead. You can only play for a few minutes per day, though, so it unfortunately isn't a time sink.