This is a nice emulator.
Speed: 10/10
Amazing. Just got my ti-89 titanium used as an upgrade from my broken ti-84+SE. Used to ti-boy by calc84maniac, i did not expect anything decent from this emulator, but i forgot that its called '68k' for a reason. It's a different processor! Pokemon Red's intro runs at about 28-30fps with a frameskip of 2. I hardly notice the frameskip. After that, you may want to increase it a bit. Be sure to disable SRAM in save states if you chose pokemon, because it takes a VERY long time to compress. Otherwise, just hope no one (e.g. your maths teacher) notices the 'compressing...' text on the screen.
Graphics: (9/10)
It's a shame there's no 'crunching' (scaling) feature, but I still am impressed! Besides a few minor graphical bugs that come with a work-in-progress (i know Ben dropped work on it but at the time this was to be a WIP), the whole game is quite good. The bugs are barely noticeable, so don't worry too much about them.
Playability: (9/10)
Would be 10 out of 10 if not for pokemon, but its an RPG with a turn-based battle system, so it's not too important.
Installation: (8/10)
Readme is not incredibly instructive; I was confused when i ran out of RAM on a ti-89 Titanium. If you just archive EVERYTHING you can, you should be fine :) Other than that, be sure to add the game rom files to a folder other than the 'main' folder.
Overall: (10/10)
'What if I told you...
THAT YOU CAN PLAY A GAMEBOY ON A TI CALCULATOR!'
What's not to like? sure, it's not a perfect emulator, but the sheer awesomeness of playing video games in math class is overwhelming. Get this program, NOW.