DuPage County
Since Meigs was lost I have tried Lansing on the south side but it takes an hour by taxi (and not through the best parts of town). Though the overnight fee was reasonable in years past, the taxi ride costs more than a train ride.
This last month, from May 16-20, I needed to work a convention at McCormick Place so I tried Dupage County Airport (KDPA). The overnight fee was only $7 for my 6A, the full service fuel was in the $5.50 range, and the FBO was very helpful to take me to the Metra commuter rail station in Geneva. With an advance call they also picked me up at the train station on my return several days later. The ticket to ride all the way downtown to the Ogilvie Transportation Center (near the 400 block of Madison Street) was $5.65 (one way). The conductor will sell you the ticket after boarding, if the train station's ticket office is closed. I was able to bring three pieces of luggage on the train, but you can bring more if need be. It's a tight fit up the stairs, but if you go to the upper deck of the train car you will find a suspended shelf that runs the full length of the car on which to store your luggage. The seats are fairly comfortable, at least as good as a taxi, and not crowded during the daytime.
It takes about an hour to ride downtown. The train departs Geneva about once per hour during the week.
It worked out pretty well for me.