We can see why you would want to avoid the high ticket prices. Screw the fact that the money goes to secure the permits that make the festival possible (the BLM Playa permit is $30,000.00). You need drinkin' money! So here is a few hints on how to sneak in to the festival.
Once you get to Gerlach, drive over the railroad tracks on the south end of the Playa. You'll see them once you get there. You can't miss them. Just please try to avoid the trains if you can. You wouldn't think it is that hard, but in 1998 two people trying to sneak into the festival somehow managed to get hit by a train. One of them shut down the tracks for 24 hours, which is technically a felony. Ironically, the ticket was far cheaper than their cars, both of which were totaled.
It might have something to do with the fact that the trains are running along at over 70 MPH with no warning. At that speed, the trains seem to come out of nowhere. My advice is that if you get high centered trying to cross the tracks, run for your goddamn life! You will have nearly no warning the train is coming and once you hear the whistle, it is too late.
Once you avoid the railroad tracks, or more specifically, the freight trains running on the railroad tracks, then you simply have to avoid the mud bogs along the southern edge. This shouldn't be difficult except for the fact that they crust over and look exactly like the hard and safe stretches of Playa. They look fine on the surface, but they will suck your car to the axles if you come close to one.
The added incentive for avoiding them is the fact that no tow truck will risk coming and saving you. Seriously. The closest they will come is the railroad tracks and only when the railroad engineers are present and only to tow away another totaled vehicle.
After avoiding the trains and the mud bogs, you are almost home clear. All you have to do is avoid three other hazards that I will not tell you about. But when you find them, However, when you find them you will know that you are really screwed. The only way to avoid these hazards is to go back through the bogs, across the railroad tracks, back to Gerlach and come in the main Burningman entrance and pay your money for a ticket.
If anyone is planning to actually sneak in, please let me know what date and time you are planning to sneak in. My e-mail address is firstname.lastname@example.org. I will not turn you in, I promise! Although, really, that would be doing you a big favor. Instead of that I to videotape your attempt. People pay good money for footage like that and I want to be there to get it all down.