You may want to file this in the drawer with The Vega Brothers, Quentin Tarantino's once-mooted prequel centred on Michael Madsen and John Travolta's characters from Reservoir Dogs and Pulp Fiction. But here goes anyway: Tarantino's considering a prequel to Inglourious Basterds, assuming that this one is a hit.
In an interview with The New York Times, Tarantino said that a prequel may happen. "I have a half-written prequel ready to go if this movie’s a smash." That's apparently about a group of African-American soldiers trapped behind enemy lines, an excised subplot from the main Basterds film.
Tarantino also mentioned that his childhood revenge fantasies always centred on the Ku Klux Klan, saying, "It’s all the same. Once the Basterds get through with Europe, they could go to the South and do it to the Kluxers in the ’50s. That’s another story you could tell.”
Now whether either of these ever happens depends a) on Inglourious Basterds doing well at the box office and b) Tarantino not getting distracted by something else first. Still, it's an interesting prospect - right?