I've come up with a new circuit in the Netherlands. It's near Zaltbommel, a 40 minutes' drive South from Utrecht. The track is 3.4 km (2.1 mi) long, and due to its rather tight nature, only suitable for smaller touring cars.
The main straight runs along some office buildings. The parking lot across from the building might serve as paddock, and the road running parallel to the straight, as pit lane.
Turn 5 is a chicane that's not on existing road, but there should be enough room for a tight right-left flick. This kink is necessary, because without it, this straight would be approx. a full kilometre (1,000 yards) long.
Next up is a few pieces of new tarmac: a left-right chicane, just at the 2 km mark, followed by a left-hander that leads back onto the existing road.
Here's a link to the track on Google maps:
http://www.gmap-pedometer.com/?r=1414110
The track is very easy to reach: the motorway on the right of the picture is the A2 from Amsterdam to Maastricht. There's a 109-room Golden Tulip Hotel right at the penultimate corner. A grandstand could be put up on the parking lot along the short straight between the second to last and last corner, and one near turns 4 and 7, too.