As the new academic year begins, beginning to intermediate students of statistics (and their instructors) may be interested in practicing with "real-life" datasets without having to learn statistical data analysis software (such as Stata or SPSS) first*, and being at a computer where such software is available.
For this, ICPSR offers Analyze Data Online using the Survey Documentation and Analysis (SDA) system, through which over 500 studies can be accessed - public opinion polls, surveys of prison inmates, voting behavior, medical and demographic information from hospital discharge records, and surveys of consumer attitudes and expectation are just a few examples. For these studies,SDA offers frequencies, crosstabulations, comparisons of means, correlations, multiple regression, and more types of analyses - all through a web browser.
Note that as of early Sep. 2009, the video tutorial on the Analyze Data Online page still shows the pre-recent-change of the ICPSR web site look at the beginning, but the SDA functions shown further into it are those currently available.
* though of course that will be important for more advanced data analysis, and the StatLab offers workshops about such software packages.