Slengpung (slengpung.com) is the collective photo album of the demoscene. The name is Norwegian slang for "a guy who fucks around" according to the introduction on an early version of the site:
The story behind slengpung is actually quite interesting. It started out with Arcane's dad getting a book called "den store skjellsordboka" for christmas, which means something like the big book of bad words. It included a lot of words you can call people, from the northern and middle parts of Norway. Among all these words, the word slengpung amused Arcane so much he told people at The Party 1999 about it. It actually means a guy who fucks around. With the word "pung" meaning your balls, and "sleng" meaning that it flings around. This itself don't lead to anything. But when XXX/Haujobb suddenly snatched up the word and started saying "Hello, my norwegian slengpung" it became a word of the party. Everyone knew what it meant no matter what country they came from. And all the people Arcane went to The Party with certainly knew the meaning of it. A couple of weeks later the idea about making a scene gallery came up and the domain www.slengpung.com was registered. It just felt natural. So all of you guys and girls out there... Enjoy!
For those interested in the demoscene, it's a fun site to browse, though it probably means more to people who have attended gatherings and consequently have more than zero chance of actually appearing in the pictures.
Source: www.slengpung.com, by way of the Wayback Machine, August 17, 2000 cache.