datasets to test clustering algorithm

From: Rajarshi Guha (rajarshi_at_presidency.com)
Date: 08/12/04 

Date: Thu, 12 Aug 2004 15:58:15 -0400

Hello, does anybody know of any freely available datasets which I could
use in the comparison of a few clustering algorithms? I know of the UCI
machine learning repository but I'm not sure which dataset would be useful
for such a comparison. I'm looking for a large dataset ( > 1000
observations) with 2 to 4 clusters.

Any pointers would be appreciated.

Thanks,
Rajarshi