The first rule of Maya is save and save often.

If Maya crashes, it tries to save your scene as a .ma in your documents and settings temp folder the default path being C:\Documents and Settings\your name \Local Settings\Temp.

If you have set the TEMP variable in your Environment Variables, the recovery file will be saved to the path in the variable instead.

You can also turn on Incremental save which can be found in the options of the save scene Under the File menu.This does not help if you never save but what it does is it creates a backup folder in the scenes directory and makes and incremental backup everytime you save so if you save a few times the same scene and then decide you needed to go back to an earlier version in that session you can (kinder like a quick undo).If you crash though the incremental saves will still be in your scenes folder ready for you to recover from the last incremental save.
This won't help you now but in future it might .