Take a yoga mat....
1) stretch out those aches and pains after a hard day's ride;
2) you can sleep on 'em;
3) good for stitting on on the side of the road (eating lunch); and
4) best of all, it provided the friction to crash start my ridiculously heavy R100GS on sudanese sand dunes... I think I'd still be there without it. Thank you purple yoga mat.
They cost about 20 bucks, so if its weighing you down or you are too manly to stretch its an easy thing to ditch, turn into spare pants, etc
Something to think about