Elastic shock cord (or bungee cord as it is sometimes known) has many uses.
3mm is great for replacing clothing drawcords and for making wristloops for gloves. Make a loop that needs to be stretched to get it over your wrist but is slightly slack when on the wrist. Leave a short section free which is knotted into a hole made in the glove or an attachment point on the glove, leaving a leash between the wrist loop and the glove about 10cm long. When working without the gloves on, the elastic loops can be slid up the arm above the elbow to get the gloves out of the way.
4mm is the stuff for making crampon, ice axe and general attachment elastics for your rucksack. For ice axes, rather than fiddle about with buckles etc for securing the shaft of your axe, thread half metre of shock cord through the attachment point and push both ends of the elastic through a flat cord lock. Now tie a knot in the end and voila - simply stretch the elastic over the axe shaft and pull the cord grip tight. A similar system can be used for attachment of crampons, camping mats etc.
5mm is mainly used for making octopus straps in conjunction with Elastic Cord Hooks.
Seal with heat if you need to cut it (a match or lighter will do).
Prices are per metre. If you want several lengths - please specify this in the comments box as you check out - or send an accompanying email. Also available in a 100m roll.