Some place out there is lissajous.exe which does what you want with a sound card. It helps to DC couple the sound card for low frequency response, but you can get away without that, But I'd get that pasta thingie and look at the sticky for sound card dacing.
So I don't get maimed on my other forum, "Long Live Pangolin!". Seriously, for a low budget solution the Spehgetti aint bad... Actually quite good.
It has a nasty learning curve, and hidden features, but LFI Player is freeware on sourceforge, and its author responds to email questions in a business day or two. It has a awesome abstract generator and will talk directly to your existing sound card when configured properly.. To access the controls for the abstacts, you must load a existing abstract, play it, and click on it to pull up the menu.
You can then save your new abstract. I'd email Mike for help before I give up on it though,its a bit under documented.
Graphics will get mangled on a non DC coupled sound card, but symmetrical abstracts for the most part have a self balencing quality and will get through Ok.
Steve