Data Mining Data Sets

Every once in a while I receive a request or see one posted on some bulletin board about data mining data sets. I have to say, I have little patience for many of these requests because a simple google (or Clusty) search will solve the problem. Nevertheless, here are four sites I've used in the past to grab data for some testing of algorithms of software packages:

There are several sites for data, including:

UC Irvine Machine Learning Repository: http://archive.ics.uci.edu/ml/

Carnegie Mellon Statlib Archive: http://lib.stat.cmu.edu/datasets/

DELVE Datasets: http://www.cs.utoronto.ca/~delve/data/datasets.html

MIT Broad Institute Cancer Datasets: http://www.broad.mit.edu/cgi-bin/cancer/datasets.cgi