Masking the address bar

Is there a way to make the url in the address bar read something else?

For instance, instead of "www.mysite.com/topic/default.aspx" to read "www.mysite.com/topic/".

I've already coded the change I need, so only need to know what and where to assign to.

I also have UrlRewrite functionality using the Context.RewritePath() if that affects anything?

 

Any help would be greatly appreciated.

Thanks, Pete.
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