James Gosling talks with Bill Venners about his current research project, code-named Jackpot, which builds annotated parse trees for programs and can help you analyze, visualize, and refactor your program.
What if you could interact with your program's AST just like you could the source code? On one hand, it might lead to interesting ways to visualize and operate against the entire system. On the other, though, a good IDE shouldn't require you to ever interact with the AST. Only now are we seeing IDEs with the kind of power we've wanted (Eclipse, etc).