My default configuration on a non-development Windows box is to run as a standard user (i.e. one that isn't in the Power Users or Administrators group.) When I first bought the MacBook, I wasn't with it enough to try this configuration.
At this point, I've learned enough, that I thought it was time to switch my login from an Admin to a Standard account. Doing so was trivial (after first creating another Admin user.) There was a little challenge of changing the ownership of some applications. It seems that apps which were installed using an installer were all owned by root, however apps which were installed using the drag & drop into /Applications method were owned by me. A quick chown -R later and everything was happy.
Except Photoshop Elements. When attempting to use any of the effects or layer styles, none of the selections show up.
The left image is from an Admin user, and the right image is from my standard login. A quick google search turned up this Mac OS X Hints article and this Adobe Forums thread. It seems that PSE users need write access to /Library/Applications Support/Adobe/Photoshop Elements/File Agent/6.0/en_US, and the two articles give several options for setting the permissions.
My first attempt was to use chmod (being somewhat command-line oriented.) Major FAIL.
Even though I can create a file in /Library/Applications Support/Adobe/Photoshop Elements/File Agent/6.0/en_US, PSE doesn't seem to be able to do it's thing with MediaDatabase.db3 (that file doesn't exist for me.) Another odd thing is that my test file (created with touch) was created with rlobrecht:admin as it's owner, instead of rlobrecht:staff. Weird. chown-ing the en_US directory to root:staff doesn't seem to help either.
Even logging in as my Admin user (which does work) I don't create the MediaDatabase.db3 file referenced above.
Back to the web for a huge RTFM moment. It seems there are two directories referenced: /Library/Application Support/Adobe/Photoshop Elements/6.0/Locale/en_US is the other one.