Slip's Music Database: MapleStory BGM & OST Collection

There were a few tracks on StudioEIM's portfolio that were quite interesting:

Kerning Square (Alternate Version)
Summer Boating (Alternate Version)
Poison Forest (Alternate Version)

All three of these tracks never made it into the game, but they were certainly considered at one point.
The Poison Forest track is completely based on my hypothesis, as there were no tags on that track whatsoever. Summer Boating had tags denoting it as "Boat Racing".

Anyway, enjoy these tracks as they bring with them a blast from the past -- a bit of nostalgia moving forward following today's reveal of MapleStory 2.

The last one gives me both that and a Temple of Time vibe.
Still nice though.