When I lived in the STL area, before 364 ever came through the region, MO 94 and Kisker Road had the worst timed left turn signal. If you missed it, you easily waited 4-5 minutes for it to turn green.
There are a few around me that take about 90 seconds on the red cycle. I haven't noticed many that are longer than that in my area anyway. The longest ones are the ones that have a green turn arrow as well.
Also in STL;
Lindbergh and Ladue is downright awful for Ladue. Lots of schools in the area (MICDS, Chaminade, Ladue HS), so the left turn lane from WB Ladue to SB Lindbergh takes 3-5 minutes to get through in rush hour. The signal used to be all protected lefts but was changed to FYAs a few years back (before the old mast arms were replaced all together). Still hasn't changed much though.
What do others think is long? I think anything in excess of 2 minutes.
There are a few on the NY 441 corridor that meet that threshold (I've even timed it), and that's long enough for me.
NJ 29 has reds that will last about 3:20 to 4 minutes long at Cass and S. Warren Streets.
I dont know if I would consider 2 minutes that long. If you're on the main road, heavy traffic can esisly congest with greens only 60-90 seconds long, so 2 minutes may be quite appropriate.
What about the light at NJ-23 and Clinton Road in West Milford? The Clinton Road that's supposedly haunted.
Barker-Barry Tunnel, (https://goo.gl/maps/ZVxBWR4uXCaMEiaC9) Golden Gate Recreational Area. "Five minute red light." They've since removed that sign.
Washtenaw at Carpenter and Hogback Roads just outside Ann Arbor. Bring a book to read. You'll wish it was only a five-minute red light, especially at two in the morning. Damn light forgets to change sometimes.
US 202 and US 1 in Delaware County, PA favors the road with less traffic. Each direction barely gets 50 seconds total (including turns). Traffic on 202 backs up through prior intersections during rush hours.