for every person who replies there will be a different answer
over the years, I've tried many things and for me only 2 things work
a tight lycra rich top that hugs you (compression type tops) - but they are too warm in summer so that's the winter solution
for summer, I cover them with tape. ther are all sorts of tape solutions from cutting up plasters, Micropore, Nip-buds (expensive) and other. my solution is to use Strapall tape which physios uses as it sticks better than anything else and doesn't sweat off. it can however be a bugger to get off if you are hairy like me so be prrepared for a bit of pulling hair pain!
vaseline, bodyglide and various other creams and unguents just wear off and are useless imho, although vas in copious amounts can be used if you forget to tape up - as I did for one London marathon and I just happened to be wearing my most chafing vest! I had to stop a few times to get more vas from the kind St Johns people ho were handing it out.
oh - and before Wilkie comes along to correct you as it's her pet hate - it's chafing, not chaffing....
Edited: 24/09/2012 at 09:25