Larry Niven's Ringworld series has multiple forms of FTL travel.
The Hyperspace Shunt:
The hyperspace shunt, an engine for faster-than-light travel, but slow enough (1 light-year per 3 days, ~122c) to keep the galaxy vast and unknown
The Quantum II Hyperspace Shunt
the new "quantum II hyperspace shunt", developed by the Puppeteers but not yet released to humans, can cross a light-year in just 1.25 minutes (~421,000c).
Though one could argue that if they are both "Hyperspace Shunts" that this isn't two different forms of FTL.
However there are also Transfer Booths and Stepping Disks that may be FTL but the wiki entry isn't clear (emphasis mine):
Point-to-point teleportation at the speed of light is possible with transfer booths (on Earth) and stepping disks (on the Puppeteer homeworld)
But the entry for Stepping Disks says:
They also have a far greater range than transfer booths, extending several Astronomical Units.
It's possible that the Transfer Booths operate exactly at the speed of light as a speed of light trip around the Earth would still feel somewhat instantaneous but if the Stepping Disks really are instantaneous then given that 1 AU is approximately 8 light minutes, and 8 minutes is far from instantaneous then the Stepping Disks would necessarily be FTL.
