metric to imperial conversion (vice versa)
if you ever need to convert a metric drawing into imperial (ie. meters to feet)... instead of using the traditional scale command, a neat trick is to insert the drawing to be converted as a block into an imperial template. all units will then be converted... when you explode the inserted block, even the dimensions will follow.

just make sure the your source drawing is in the proper units before inserting it to the template you want it to be converted into...

this works best in working with large drawings since it will take lesser time for your computer to process the command and dimensions are also adjusted...