Today I ran into a bit of an issue in a SharePoint server farm environment where I added a web part to a page, but for the life of me I couldn't delete it. I clicked the 'X' button, I tried to edit properties, I tried to delete from the edit pull down menu, but nada! I tried from the load balanced URL and from the Index Server but no dice. I did a quick google search and hit this helpful link,
http://www.sharepointblogs.com/nrdev/archive/2007/02/08/tip-easily-get-to-the-webpart-maintenance-page-for-any-sharepoint-site-url.aspx
Basically by adding "Contents=1" as a query string variable to any page, you'll go directly to the web part maintenance page for that page.
Ex. http://{site url}/pagewithproblemwebpart.aspx?contents=1 will take you to the maintenance page.
Update 7/7/2008
The url above will actually redirect you to the following url.
Ex. http://{site url}/_layouts/1033/spcontnt.aspx?&url=pagewithproblemwebpart.aspx
Between the two url's I provided you should be able to deal with problem web parts and get back to a working page with little downtime.
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