A small rare earth dental magnet (the size of a pulp chamber, typically 0.2g) can easily suspend a 37g steel weight...a force to weight ratio of 185:1!
Source: Neilburger E, Death by magnets: An unrecognized danger in dentistry, General Dentistry, May/Jun 2008, Vol 56, No 4, pg 346-7.
Hans Skariah, B.Sc., DMD
Promenade Court Dental Health Group in Mississauga
2233 Hurontario St., Mississauga, ON, Canada
(1/2 km north of the QEW in the Dome Building)