I
love this travel insurance company:
World Nomads - Travel Insurance Quote
It covers me for most any activities that I enjoy doing. Be sure to read the fine print on insurance coverage. I found that the AXA insurance doesn't cover you terribly well if you plan activities much more adventurous on your vacation than sitting around in a hotel lobby or strolling about in the shopping mall.
The bonus with World Nomads is you can buy it from any computer using a credit card.
(Hint: Do a google search for World Nomads discount code or promo code to easily get yourself a 5% to 7% discount on their rates).
