Java Framework Ideas
For a project I'm doing over the summer, I have to come up with a simple java framework for any specific application domain. (And it can't be a 2-D table-based game like minesweeper because I already made that). 

But I'm having a lot of trouble coming up with any ideas for what to make. Does anyone have any suggestions for a simple framework that people could create simple plugins for? (Preferably using only java and swing stuff).

Thanks in advance! I've been stuck for days and I can't think of anything! 
Java Framework Ideas
===

For a project I'm doing over the summer, I have to come up with a simple java framework for any specific application domain. (And it can't be a 2-D table-based game like minesweeper because I already made that). 

But I'm having a lot of trouble coming up with any ideas for what to make. Does anyone have any suggestions for a simple framework that people could create simple plugins for? (Preferably using only java and swing stuff).

Thanks in advance! I've been stuck for days and I can't think of anything! 