This is absolutely possible, but your question is a little too vague to give you specifics. You'll need to look into using the cffile tag to get the file off of disk. If we assume that your popup takes a date through the URL, and your files are formatted as "yyyy-mm-dd.txt" in a folder called "myfiles" at the sae level as your popup, then you could do something like this:
<cffile action="read" file="#ExpandPath("myfiles/#DateFormat(URL.myDate, "yyyy-mm-dd")#.txt" variable="myFileContent" />
Then, to output the content of the file:
You can find more information on the cffile tag here:
Hope that helps,
Adobe Community Expert
Message was edited by: Daniel Short. Added syntax highlighting.