SR 9336 - Not sure how or why they came up with that number, it dead-ends at Everglades National Park (a good reason, at least).
SR 17 (and CR 17) - exists in about 10 pieces, and alternates.
Some of them are less than a mile in length: SR 844, 849, 970 for example.
There's also the unsigned diagonal routes like 500, 600, and 700 that are tricky to complete.
Also plenty of "look-it's-a-county-road, now it's a state-road, no wait...it's a county road again" examples: SR 15, 884, et cetera.
Lots of maps show county roads as state roads, just collect 'em all!