Prefix all you forms you want to select with cfrm:
Ensure your control's RowSourceType is set to Table/Query. Open up the query design grid from your combobox or listbox's RowSource.
Switch to SQL View:
An SQL Statement like this should finish it off...
SELECT Mid(Name, 5) AS FormNames
FROM MSysObjects
WHERE Left(Name, 4) = "cfrm"
ORDER BY Mid(Name, 5);