Configure QuickLook to open particular files I'm wondering if there's a way to get QuickLook open up files it doesn't recognize.

For example, I'd like to be able to have QuickLook view .mailsignature files in the basic text viewer. Any suggestions?
You might be able to open them with QLStephen which opens all kinds of files that are plain text. 

I am hesitant to recommend it since it will try to open every file for which you don't have another plugin as plain text which is not helpful. It has a blacklist but I found myself constantly adding things to said list which makes it kind of bothersome to use.