Find, Find, Everywhere a Find...

AutoCAD's FIND command is pretty handy in way you might not expect. Here's an example:

Say you want to change a bunch of hangers from #11 to #16 -

1. Turn off all but the Hangers layer
2. Type in Find
3. Type in 11 in the Find text string field (do not enter the # sign - that is a wildcard character)
4. Type in 16 in the Replace with field (ditto on the # sign)
5. Pick the Select objects button on the upper right and select all the hangers. This ensures that you don't replace the attributes of other objects like pipe sizes by accident.
6. Pick Replace All

Ta-da!

Another example - say you need to submit a drawing that does not have the ½ or ¼ symbols in it.
Turn off all but the pipe sizes and hangers and replace \ with _1/2 and [[] with _1/4 where _ is a blank space.