Stoly comes in 151 proof in some countries. Quite a few rums are made overproof and 151 seems to be the magic value (perhaps due to tax laws -- though the high proofs become close to undrinkable unless diluted as they dessicate the mouth too much). Tea rum is often made at 80% (160 proof) as a teaspoonful is added to a cup of tea

The practical limit is 95% or 190 proof -- removing the rest of the water content gets to be quite expensive and is only done for laboratory purposes. Also somewhat dangerous as it can kill cells on contact (above 70% ethanol is a good bactericide).