REQ: Live mashup performance tool

I have an idea for a software that I would love to use to do live mashup performances. It’s based on experiences I’ve had with different types of software and hardware tools, but none has the exact functionality I’m looking for. The inspiration I got comes from different sources:

The goal here would be to improvise: just like a DJ does not know up front what tracks he’s gonna play in what order, the live mashup DJ wouldn’t know what his set is gonna be like. He just arrives with his portable PC , starts with e.g. a Jon Cutler acapella over Prince’s Controversy beat, throws in some Justin Timberlake vocals, keyboards from Depeche Mode and a De La Soul sample, goes to the break with Michael Jackson’s “Ma ma sa, ma ma coo sa” and Daft Punk with a wah-wah filter. Whatever.

So the software I have in mind would work in the following way:

Does something like this already exist? Would Sony or Ableton be close to creating it?

💬 music