China should have 5 time zones, but only uses on based on Beijing. So in Urumqi in Western China, sunrise can be as late as 10:00 and it can still be broad daylight as late as 21:00
With the various islands of Kiribati traditionally on different sides of the International Date Line, Kiribati shifted the line in 1994 creating GMT 13 and GMT 14. This is so offset that it could be 3 calander days at the same time: 10:30 Saturday in the UK, 23:30 Friday in Niue and 00:30 Sunday in Kiribati's Line Islands
This half hour time zone has one unique feature that sets itself apart from others: Daylight Savings Time. When it's time to set clocks for DST, Lord Howe Island advances, not by a full hour, but by a half hour. The only place in the world to do so.
With ideal time zones being referenced by every 15 degrees longitude from the Prime Meridian, Argentina should be GMT -4, but it is GMT -3, which gives it more daylight.
What makes this time zone unique other than being further behind all others? Nobody useses it. It's an unofficial time zone containing only uninhabited islands such as Baker Island