Alfred is one of the most useful tools I think I own on my Mac it speeds up production speeds like nothing you've ever seen. One of my biggest gripes with Mac OS X though is the faff it takes to show hidden files / folders (including 'Library' in Lion).
As a result of this I have made an Alfred extension to give you the ability to show / hide hidden files. All you need to do is open Alfred and enter 'hiddenfiles show' or 'hiddenfiles hide', it's as easy as that!
Update v.2.0
The extention is now a tiny bit more clever. Now if you just type 'hiddenfiles' without a parameter it will toggle the hidden file and folder visibility. The old method of forcing the visibility is still working too.
Version 2.0 Download for Alfred v1
Version 2.0 Download for Alfred v2
Note: The Alfred v2 version supports shortcuts. Command + Option + H toggles hidden files.
Screenshots
Toggle visibility
Force hide
Force show
Older Versions
For those of you who like old things. Version 1.0 Download