I am fairly new to this community (been here since December, 2006), but I have played Marathon since 1998. In April, 2007, I released the first version of the netpack, "Sovereignty."
Sovereignty is a net-mappack containing 8 maps. It has received great feedback on Fileball, the Pfhorums, and Simplici7y (map sharing).
I am currently not working on my new mappack, which has about 5 maps so far.
P.S. I are the smartest 8 year old ever.