Date a guy - err... no. One shouldn't mess with people's feelings.
Swim across the English channel - That's not something I could do like that. But it might be something worth doing in the further future. Not kidding.
Having set my alarm at random - That's not really trying something new is it. Nor is it doing something. And if you mean not sleeping a lot than it's far from doing someting new.
Pick a fight - Has happened already. But I don't want to pick a fight with someone as I don't want to be thrown out of the gymn either, plus it's kinda too illegal. Don't want to do stuff to make other hurt or myself too much.
Ventriloquism in night clubs - Verry silly but can be done I'll ad it to the possibilities list.