Tip for all After Effects users!

If the save dialogue box pops up randomly, for gods sake use it to save a backup copy of your project!

I've often found that if AE crashes unexpectedly it will pop up the save window without necessarily warning you that it has crashed (which it usually does when it crashes) - if you close the window it will usually be followed by some evil Runtime error and AE disappearing!

(The first few times this happened, I crossed off the window, only to lose my work! Needless to say, I've learned to always save a backup copy when this happens!)