FL Cet is the shortest period eclipsing Polar known.  It's P_orb is 87.13 minutes, and it's eclipses are around 5 magnitudes deep with a 6.5 minute duration.

 

CCD observations obtained with the Bradford Robotic Telescope, and V-band observations obtained with the Sonoita Research Observatory 35cm and 50cm telescopes (through the AAVSO).