Slouching Towards Bedlam is a highly-praised interactive fiction game that won the first place in the 2003 Interactive Fiction Competition. It is a collaboration between two authors: Daniel Ravipinto (who was known before for his game Tapestry) and Star Foster (a newcomer to IF scene). Slouching Towards Bedlam was nominated for six 2003 XYZZY Awards, winning two: Best Game and Best Individual NPC (for the protagonist's cybernetic assistant, Triage). The game takes place in a steampunk Victorian era setting. Its title is inspired by a line from The Second Coming, a well-known poem by W.B. Yeats.
As of 2006, the mean score of 8.39 that this game received remains the highest in IF Competition's history. (Note that this statistic wasn't available for the first four competitions, from 1995 to 1998 inclusive.)
Freeware :: Adventure
Z Machine :: Interpreters

Baf's Guide to the IF Archive - Capsule review by Emily Short, game information, and downloads.
SPAG Review - In short: you must play this game. By Jessica Knosh.