The full name is Petteri Lamuranta.
Pelulamu was a fictional 12-year old "computer expert". In truth, he was created by PWP hacker group to parody these l33t d00dz who are polluting the precious web space. He can sometimes be seen in ircnet, and had a web page in http://pelulamu.cjb.net/.
The page had a hilarious section about Linux ("Microsotf (sic) sucks!") and "My Father's Elections Pages!" ("Microsoft's possibilities in Finland must be extended")