I need something epic and amazing and adventurous and exotic and crazy to do this winter... ideas?

k, so basically, I want the adventure of a lifetime. I love being outdoors and being challenged. I was thinking maybe a cycling trip in the southern himisphere or near the equator? or maybe a long distance hike somewhere? also consittered teaching english or wwoofing in nepal, or cycling accross brasil? im open to anything and I habe october till april... ideas? also I love motorbiking, sea kayaking and anything adventurous like that. last winter I hitchhiked around australia so I need something equally if not more epic and awesome!!!