If you have the old Signal Computing Train Dispatcher (game) software, there was a territory covering the Sacramento-Roseville-Marysville/Oroville "Triangle" that would occasionally throw a 9000-foot drag (top speed 40 mph, long reaction time) at you (all the sidings were less than 7000' - probably SP or early UP era). If you had "realism" fully turned on (random arrival times, breakdowns, hotboxes, etc.) then guaranteed that beast would show up at Polk about the time a pile of Z's and a late Amtrak had to get pushed through, and one or more of your switches failed. Even if everything was set up simple (arrivals on time, no breakdowns) it could get interesting if you weren't really paying attention. It usually came in at Polk but had to go out through Oroville (your choice how you routed it), but if "realism" was turned on it would occasionally appear on the WP line from the south. Fun...