All this talk of boiling strings, without ever addressing the finer points of the process; here are lessons learned from both the culinary arts and the nuclear energy sector, which have drastically improved string-boiling techniques in recent years...
With heavy gauge strings, it's best to hard-boil 'em.
However, lighter gauges you can get away with a simple, quick parboil.
Round-wounds are best brought to a rolling boil, but no longer than 5 minuets [sic] worth.
Coated strings, of course require film boiling.
Ground-wounds work best with transition boiling.
Gut strings on double-basses should only be boiled with natural convection.
Despite rumours to the contrary, it is perfectly safe to bring nickel-core strings to a nucleate-boil.
Extra-long strings for fan-fret instruments or downtuned instruments should be boiled at lower temperatures; since water will boil just below the temperature of its container's point of ignition, it is recommended you boil extended-range strings in a container made of hide, such as an all-natural wine-skin.
Rubber-based such as those found on Uke-basses, or synthetic strings on uprights, should never be brought to a full-boil, but rather a simmer — rapid simmer for rubber and a slow simmer for synthetic.
An alternative to boiling is steaming, but as this method is much harder to control (temperature, density, saturation, differences in strings types etc) the results will vary and very often may be unsatisfactory.