Multimatic is a post-processing tool: it does not run on your camera, and does not require any specific camera or device to be used. You can use it with images from any source. The strips at the top and bottom of this page, for example, were made by using Multimatic on its own output.
Multimatic does not "fake a Lomo". You can use it to get similar effects as some of their multi-lens cameras, but the final result is highly dependant upon what images you use. Lomos generally have very wide lenses and very eccentric contrast and colour, which is a major component of the distinctive style. Multimatic does not make your photos look like Lomo photos.
There is some more discussion about Multimatic here, if you like that.
Multimatic was written by Casey in March 2005. You can contact Casey by emailing casey at caseyporn dot com.