Well, it's not really a IIDX simulator... it's a combination of IIDX and Pong that uses simfiles, born out of a class assignment to make a Pong game. It's more fun than it sounds. (Ironically, I can't even turn this in as my Pong project, because it's lacking a lot of required features, so I'll have to make another basic Pong game and turn this in as extra credit)
Anyways, gameplay video and download link at the (hastily thrown-together)
pongmaniaIIDX homepage. The download includes a default skin and 10 pongmaniaIIDX simfiles converted from BME files, with videos.
Just a little note, it uses entirely software graphics, so songs with lots of keysounds could start to lag and go offsync horribly. If you find this happening often and/or it really annoys you, just edit the config.dat file to read "movies=off". This will disable the movies which really helps with performance.
Also, if you try to convert other BME files to work with pongmaniaIIDX, make sure you realize that the shitty little tool I made to convert BMEs to the PMN files used by my game doesn't support BPM changes. If someone else wants to make a converter that does, be my guest, but I'm probably not going to touch it for a while so don't expect an updated converter any time soon.
My IIDX... err... "simulator" thingy 
