Tired of using that old standard of 299 792 458m/s for the speed of light?
Is c or 3.00x10^8m/s all you ever write?  Then try some of these new
measures... amaze your friends, annoy your physics professors!

     7.0x10^5 astronomical units/sunspot cycle
 2.9267x10^11 bolts/jovian rotational period
  3.613x10^19 calibers/lunar year
  4.323x10^17 cubits/century
 2.0965x10^18 Didot picas/year
 8.2772x10^19 ells/eon
 1.6392x10^-7 fathoms/femtosecond
 3.2612x10^13 (fermi)(cesium standard frequency)
 1.8026x10^12 furlongs/fortnight
 6.4825x10^14 geelongs/((tex)(tropical year))
 1.7846x10^15 hands/week
 1.0326x10^16 inches/venusian hour
 2.4743x10^11 international cable lengths/ionian day
  5.8275x10^8 knots
  6.2094x10^4 leauges/second
 1.4163x10^30 lines/exosecond  
   3.80x10^15 links/lunar month
   5.77x10^-7 megaparsecs/martian year
 3.7248x10^23 mils/millenium
 4.5323x10^14 nails/day
 1.7063x10^12 nautical leauges/leapyear
9.4870x10^-17 nautical miles/nanosecond
 1.3031x10^19 paces/millenium
9.7156x10^-21 parsecs/picosecond
 1.8812x10^15 (perches || poles || rods)/sidereal year
 4.7849x10^15 ropes/month
 1.1300x10^14 spans/sidereal day
 4.6122x10^19 squares/second (.65 micron process)
 8.2911x10^16 US printer's points/Solarian day
 2.4644x10^15 US survey feet/leapyear February
 9.4417x10^28 X-Units/mean calendar year
 1.0347x10^16 yards/year

__________________________________________
All units from the HP48 Equation Library or the CRC Handbook of Chemistry
and Physics, 71st Ed (1990-91).

Since I hardly qualify as a math.wizard, I recommend checking all values
before actually using them.