I was very excited to see that the good folks over at BlueDragon have gotten a version of UpdatePanel to work for ColdFusion. This uses the same client side infrastructure in the Microsoft AJAX Library that ASP.NET's UpdatePanel uses.
Here is an example of what it looks like to in the markup
<h3>Start Time: <cfoutput>#timeformat(now(),"long")#</cfoutput></h3>
<input type="submit" value="update time">
And check out this live demo
Catch all the details on Vince's blog...