If you Tab through a web form (such as the one on the hint submission page) with Safari or another WebKit-enabled browser, and then hit the down-arrow key when the drop-down menu highlights, you can select all the options, and even jump to a selection by typing out the first few letters of what you want!
kirkmc adds: I couldn't find anything in the archives about this, though I have a feeling it has probably been hinted before. Note that you can also use the spacebar to select drop-down menus; press the spacebar to display the menu, use the up- or down-arrow keys to move around, then press Enter to confirm your selection.

