To bump a thread on an Internet forum is to post a reply to it purely in order to raise the thread's profile. This will typically return it to the top of the list of active threads. BUMP is sometimes used as a backronym for "Bring Up My Post/Post count" or as a recursive acronym "Bump Up My Post".
Thread bumping is commonly considered a breach of netiquette and some moderated forums forbid it. Users may get around that by posting what is ostensibly a genuine reply. Sometimes this will mockingly contain the word "bump" in it, such as "Wandering the forum, he bumps into this thread...", or be a trivial question or response such as "Anyone?".
http://en.wikipedia.org/wiki/BUMP
BTTT - Bump To The Top
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Been There Tried That
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