I have a raspberry pi B+ set up in a server configuration and it connects to internet successfully over Wifi with a USB dongle.
My other pi (an A+) has always been located downstairs in the garage, getting an internet connection from an ethernet cable to my modem.
Though having to run downstairs to modify the pi or disconnect it is kinda frustrating when doing it multiple times a day.
I wondered if there was a way that my B+ could share its wifi connection to my A+ over ethernet. The A+ would connect with an ethernet cable to the B+ ethernet port then.
I also have a 10/100 switch laying around if needed.