Mac OS X keyboard character/symbol that falls last alphabetically?

When browsing files in the Mac OS X Finder, I often add an underscore to a filename to pop it to the top of alphabetically sorted views, especially Column View – like so: _my folder.

I am trying to find the inverse symbol or character to drop an item to the bottom of a list. I even went through a process of adding all the odd characters one gets when using the option keys and such, but no luck. Does anyone know of a symbol or character that will make this happen?

Bonus points if it can be invoked via keyboard, instead of having to do so from the Character Palette.