Back in the days when Windows 98 ran on MS-DOS, I found a small free game called "Gridlock". It ran in DOS. It only used the four CGA colors of red, green, blue, yellow and was otherwise black and white. It was a simple looking game, but it proved very challenging. I've searched for it on the net, but only found other games called "Gridlock" which aren't the same at all. I may still have a copy of the game stored on one of my old Iomega zipdisks I used to use to backup my system. My zip drive isn't working and not connected to my current machines. I may try searching through them all someday.
At any rate, the game was all about traffic control. There was a fixed layout of one-lane, two-lane, three-lane, four-lane and multiple lane roads. There were a few blocks on the layout representing building destinations spreadout over the city, such as a shopping mall, etc.
Your first task was to setup the traffic control network. You placed stop signs (2-way and 4-way stops), and traffic signals, some with left turn siganals, others without the left turn signal. Some intersections had a left turn lane. You then programmed the traffic signal lights, you set the duration for each of the green lights and the left turn signals.
Once you had your signals all programmed and all your stop signs placed you set the amount of traffic. Then you turned on the game. The traffic was automatically generated and started flowing into view from the edge of the screen on each of the roads in varying amounts and a slightly different speeds.
The amount of traffic would gradually increase up to the limit you set. The vehicles were represented by small yellow, blue, red and green rectangles, except for the one lone target vehicle which was white and would arrive on the map at a random moment. It would have a specific destination on the map to get.
It would navigate through the streets along with the rest of the vehicles obeying all the lights and traffic signals you placed until it arrived at it's destination.
However, if you didn't do a good job of setting up the traffic controls and programming the lights, traffic might start getting backed up and block other intersections preventing other traffic from crossing or turning onto another road.
At this point you begin fine tuning your traffic lights and changing the stop signs to provide the most efficient flow to the traffic trying clear any backup or blockage. However, it usually led to total gridlock where most of the cars were trapped in huge blockages. You tried to prevent this state as long as possible and your time is recorded.
The game had a fun but pointless "night mode" where you could make all the little vehicles turn on their headlights (two little white pixels) on their front end.
I would spend hours trying and retrying signal light programming. It proved very addictive. Searching for this game on the net evently led me to the discovery of "Traffic Giant", which has similar functions, but to a much simpler degree.
If someone ever would turn that old DOS game into one that ran on Windows I'd buy it in a second. The traffic signal programming was very engaging and challenging. Eureaka! I've found it!
After all these years I finally found another copy of the game above. I refined my google search by elimnating results including "parking", "android", "iphone" and "buster" (for Gridlock Buster -> an entertaining online traffic control game @ http://www.its.umn.edu/GridlockBuster/game/
search on: "traffic control game gridlock -parking -android -buster -iphone" (omit quotes)
I found a copy of it at: http://www.demu.org/pages/view.php?ref=1107
You need a way to run it in DOS on your system to play it. You may be able to use a program like DOSBOX that simulates MS-DOS..
Like I said, it's not much on looks but I found it very addictive. It's just amazing how entertaining a game that is only 98KB in size can be! Tilted Mill make me a updated Windows version of this game, please! <Grin>