Access 2007 Runtime is for free now...
... The Access 2007 Runtime is similar to previous runtimes in that all design-related UI is either removed or disabled. However, there is one major change: we will be offering the Access 2007 Runtime as a free download. You will not need to buy Visual STudio Tool for Office (VSTO) in order to redistribute the Access 2007 Runtime. You can freely redistribute it or just point people to the download on Microsoft.com.
For Access 2003, you still need to have VSTO 2005
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