An especially good idea if you have any 'vintage' equipment (like I do)... I have seen almost "night and day" differences in speaker performance after a recap.
Recapping a speaker crossover is very easy to do (in most cases); all you need is some basic tools and some soldering equipment.
Certainly something to look at if your amplifiers, etc. are of the vintage variety as well - although recapping an amp or receiver is a bit more involved and sometimes best left to a professional....