A quick Metromix search yielded the Rock Bottom Brew Pub on Diehl in Warrenville (really NW Naperville) and Molly Malone's in Forest Park, both of which are open until 2am. Bally Doyle in Downers, Bar Louis in N'ville, both open until 1am, and lots more, including one of VI's faves, Hugo's Frog Bar now in N'ville, open til midnight.
Check it out,
www.metromix.com in the dining section, I used the search function for west suburbs and late night.
One of my current N'ville faves is Tango. Pretty good South American Steakhouse (not great, but reliably good), good prices, and they get 1/2 the business of the lousy and more expensive places all around. Open until midnight.
I imagine there are a number of places along Ogden as one travels east through Downers Grove and Westmont, such as the Omega (open 24 hours), that stay open late.
Lots of options.
d
Feeling (south) loopy