If you created reports using Visual Studio 2008 and Crystal Reports 2008 Basic (the one included with VS) and you want to deploy your app on a server, you'll also need to deploy the CR runtime. Your first reaction might be to go to the Business Objects Website and download the CR 2008 runtime.
http://support.businessobjects.com/downloads/runtime.asp#08
Well, that's the wrong runtime. That one is for the "full" version of CR 2008 (version 12). The CR included with VS 2008 is the basic one (version 10.5).
So where do I get the basic (10.5) runtime? It's right on your machine:
C:\Program Files\Microsoft SDKs\Windows\v6.0A\Bootstrapper\Packages\CrystalReports10_5