The yellow thing with the "i" in it is referred to as a sticky. It keeps the topic in place so it doesn't move as other topics are added or responded to.
The flashing triangle is for a topic with more than 25 responses or 150 views.
Hope that helps!
P.S. Stickys can only be placed by moderators/administrators. Both of these things are common to moderated discussion boards on the Web.
Edited by Tinman (10/18/08 10:39 AM)
Edit Reason: Adding P.S.
"I finally have my heart!"
To the perps: Don't worry about me coming after you. But you damn well better watch out for God! "Vengeance is mine", saith the Lord