Hi All
A friend and I are travelling from Aus to Las Vegas in March to celebrate my [mumbletymumble] birthday.
The question/s I have revolves around tipping.
Cab / Taxis - what's a reasonable tip amount?
Bellhops/porters etc - again, what's a reasonable amount? ? NB we're staying at a Marriott on the Strip, if that makes any difference. I just don't want to be a cheap chintzy tourist!

I'm reasonably happy that I have the whole food tipping thing down from reading other threads on here, so that's not a problem.
And lastly, who else would we tip? We're planning on a few shows, a few casinos, a helicopter trip over the Grand Canyon, a (self-drive) trip to Arizona to meet a friend, and general touristy sort of things.
Thanks for any help!