SharePoint 2007 does not provide this experience OOB. You will have to customize this requirement via programming.
I found a similar post on ASP.NET forum, you might be interested in: http://forums.asp.net/p/838714/838714.aspx
Among the replies, Fredrik Normén(MVP) provides the general idea on how to implement this feature in SharePoint: override CatalogPartChrome, CatalogZone and WebPartZone.
Basically, you’ll have to override most of the web part base classes. For more information on these classes, please visit: http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.webparts.aspx