I write tools to interact with games - ctrl+p to do a price lookup for item under mouse, track which cards have been played/are in your deck, that sort of thing - and it'd be really useful there. DLL injection is kind of a pain (and it can be detected as cheating, which this little framework probably doesn't solve), so the fastest route for prototyping ideas tends to be AutoHotKey or something else that can spawn tooltips easily on top of D3D windows. Obviously that has tons of drawbacks, so if this is quick & easy and runs on a 'real' platform like .NET, it'd be a lot more powerful.

Some people suggest it is mostly for "hacks". I disagree. One example I give to people is an overlay I made presents all text messages, skype message, forum private messages, etc in a mid size transparent overlay to toggle on/off and some buttons/input box to reply.

Now while in-game I can quickly reply to things and not juggle browsers, tabs, apps, etc with alt tab.

Demos? Tutorials? Cutting and pasting stuff for videos?

Game cheats for people who don't want to hook the game renderer.