For what purpose do you need the chart (considering it "doesn't have to be current")?
Just for playing-around-purposes, you could print one from MS2004. It won't have the standard format and will miss details, but all the navaids and airways should be on it. See
http://www.microsoft.com/games/flightsimulator/
AOPA also have up-to-date approach plates available for free download, but to members only. You could get a free student membership. See
www.aopa.com.
The only source I know for current, complete, digital low-altitude enroute charts is JeppView. See
www.jeppesen.com.
Good luck,
KK.