Here’s a quick tip:

The Force.com IDE allows you to deploy reports from one salesforce.com org to another. This is very useful if you’re a consultant like us, but also if you test changes in your sandbox before putting them into production. When it comes to Reports, you can only migrate reports from custom folders. This means you can NOT deploy reports that are stored in the Unfiled Public Reports or My Custom Reports folders.

Besides deploying reports, you can also modify reports, but it might just be easier to do it from within salesforce.com. One additional benefit to working with Reports this way is that you can index these files in GoogleDesktop or any other desktop search engine and then find which Reports reference a specific field or value before making a change. This is really useful when you have filters on RecordType names and want to change these names to fit a new naming convention.