Yeah...my username on a lot of sites is either Silent Memento (in one case, with no spaces between the two words) or Memento, for short (prefer the latter).
You see, I dedicated this username to my uncle (well, he was technically a cousin, but my dad grew up almost entirely in his family), who was probably the only person at the time who thought that I had a chance to become a writer. He kept encouraging me, kept lifting up my spirits when I thought that I hadn't done a great job, etc. Probably the nicest man I've ever known...and he died of a massive heart attack at the age of forty.
I already had a username on the site I wrote on, but I figured that since I had wrote two terrible stories (and the username I had before was utterly stupid anyway; I won't even get into it), that I should probably reinvent who I was as an author, which included changing my penname. So - on the advice of someone who was a friend at the time - I decided to use two words that were dedicated to my uncle. Silent Memento equals "Quiet Keepsake". In other words, memories. And since the word "memento" is very close to "memories" as it is, the username just fit, you know?