Posting a Link
Some of you use HTML in the chatter, which is fine. The problem is you don't target your link, and it then opens in the chatter window. Here's how to do it properly (I do this in comments and journals too):
<a href='http://www.example.com/page.html' target='_blank'>link name</a>
target= tells the browser that this link is intended for a new window (or tab if you have Mozilla set up that way). It's a good thing, really.