JNA (http://jna.dev.java.net) makes it "stupidly easy" to access native libraries. There are included demos on cross-platform non-rectangular windows, "move to trash" functionality, and a windows-only file modification monitor.
I wrote this stuff to make it easy to experiment with different native APIs from within Java, and it works in w32, linux, and OSX.
No more JNI compilation hassles. |