Google Fusion Tables is a great way to share public data.
Here's a table with data of the Utah Baseline Population Projections developed by Utah's Governor's Office of Planning and Budget. Fusion Tables provides an easy-to-use interface for uploading data, whether you do it from an existing Google Spreadsheet, .xls file, of comma-delimited file, you can have the table ready to go in a few seconds. Users can then analyze the data online, download it to a variety of formats, embed it in another site, etc.
Here's chart created and embedded using the population projection data. It's nice because you can mouse over any of the data bars and get the exact number associated with it: