Seoul National University Museum
OMA/Rem Koolhaas - Seoul National University Museum :: arcspace.com
This is a building I visited last year - inside and out, but was unfortunately unable to take the interior shots shown in this Arcspace entry. Definitely fun though very much a visual one-liner with the large cantilever emphasising the simple rhomboid form as shown by the near end in the photo.
Having visited this and the Casa da Musica in Porto, and been impressed by both these little jewels, I find it hard to imagine that this is the OMA outfit responsible for their proposed Louisville fugly building. (See the earlier post on eyesore of the month web site).