Have created a github repository ( https://github.com/hendrikboom3/LudumDare45.git/ ) to track progress, and post semiworking versions of my game-to-be as they become semiworking. I'm now guessing I'll be using HTML5 with Javascript, possibly with WebGL (for graphics) or pure text I/O (for an old-fashioned text game). We'll see.
I've hardly ever programmed anything in Javascript, but have used OpenGL. We'll see.
Hosting may end up being on my personal website on my home server, though I fear having too many people accessing it simultaneously. We'll see.
And it may go down for a few days in the coming month as I move the site to new hardware. Again, we'll see.
I have no idea what the game will be. Though if no ideas come to me, I may end up porting one of my old games (written in Modula 3 or in OCaml) to Javascript. Something I'd like to do anyway, but I suspect three days won't be enough time for that.
-- hendrik