I met my husband aboard a Quark ship on our way from Ushuaia to Antarctica. Trip changed my life! We both want to go back at some point in the future as well. It's truly the most spectacular place either of us has ever been.

Fortunately, it's now no longer a possibility to go on the large cruise ships. It's small ships only, and as others have mentioned, this is a good thing. It means you get the maximum ice time possible as there is a limit of 100pp on the ice at a time. Trust me - you'll want as much time as you can get! It takes hours to climb up the massive snow drift hill....and minutes to slide down on your bootie!

Also there are only a handful of actual operators for the cruise ships - and a whole host of other tour agencies taking a cut to sell slots on those few ships. Look at the actual ship owners websites for pricing and availability to cut out the middle man. I know of two owners - Gap (wouldn't recommend) and Quark (highly recommend). There are a couple of others that were listed in Ushuaia, but I can't recall the names.

If you have a specialty skill you could work the ships for a free ride - such as a MD, geologist, marine biologist, etc but you would have to commit to multiple trips or even the whole season. Speaking of, early in the season (late Nov - early Dec) is penguin mating season. Late is when the chicks hatch. So pick what you want to see and go. It will be amazing no matter what!