Terraria is a great game that can really appeal to all audiences. With hundreds of hours spent on this game crafting, building, exploring and fighting, it was no doubt worth the few dollars it cost me.

A really fun reverse tower defense game in which you command troops attempting to get past defenses. Easy to learn but takes a lot of practice and tweaking of your formation and tactics to get the best score! Certainly worth checking out for how cheap it is, and it even exists on iOS!

A well done top-down shooter by Valve and for free, how can you go wrong?