that's under tested. If you've wandered into an area that someone else is responsible for testing, share your findings with him, and take advantage of his specialized knowledge about the best way to address problems in that area.
You may be wondering why I didn't suggest using this checklist right after you've filed a bug report rather than waiting until the bug is fixed. Some of these tips may help you further isolate a bug you've found or to find more bugs based on a bug you just reported. However, I suggest using the checklist after a bug is fixed because a design decision has been made at that point. Once you know how one bug has been fixed, you have valuable information about the scope of the fix that is hard to predict when you first report a bug. Once you know the boundaries of where the fix has been applied, you're ready to explore those boundaries with additional testing ideas.
These ideas have helped me to submit a relentless onslaught of bug reports. The developers' best hope is that the severity of the bugs is decreasing on average as the number of open bugs continues to rise. I hope you can use some of these ideas to make your own bug reports multiply.