In rec.bicycles.misc Benjamin Lewis wrote:

- some bar-end shifters can be toggled between indexed/friction mode. I
have such a shifter, but it has never gone out of adjustment during a
ride, so I've never used the friction mode.

It's rather handy when you've trashed your rear wheel and don't feel
like fiddling with swapping cassettes on the "spare" wheel that has
an 8 speed cassette instead of a 9 speed. *cough* Of course, if the
"spare" wheel comes from your wife's bike, it might be wise to fix that
wheel up a little expeditiously.

--
Dane Buson - z u v e m b i @ u n i x b i g o t s . o r g
"Love is a snowmobile racing across the tundra and then suddenly it flips
over, pinning you underneath. At night, the ice weasels come."
--Matt Groening