[Steve][1] talks about un-styling of the text on the clipboard for pasting into other apps. As he rightly points out some apps support this natively. For the rest, here’s a simple shell script that I’ve saved as a background app via [Platypus][2].
#!/bin/sh
pbpaste | pbcopy
After copying text I just run this background app from any one of several application launchers. My current favorite is [Namely][3].
[1]:http://houseofwarwick.com/entries/00000042.html
[2]:http://www.sveinbjorn.org/platypus
[3]:http://homepage.mac.com/asagoo/namely/index.html