Chalk? Ambivilent. I'm going to start bringing my own merely to combat the next substance...

Tacky? I hate this stuff. It increases grip but at the price of control. I never use it and can't stand it. I smear dirt of grass all over the handles to take down some of the tack other people leave all over it.

Gloves? I like 'em for some events, not for other. I wear cloth gloves that have a latex rubber palm and fingers. You usually find them at Home Depot or Walmart, usually with a bright blue palm but I have some grey rubber ones too.
They are super grippy and give you absolute control. I can hold on when I want to and let go when I want to, unlike tacky.

I eschew gloves for the weight throws, I only use them for hammer and caber. On the weight throws I have better grip with my bare hands.

This does make an excellent idea for a new post, however it will have to wait a couple days as I just got back from Rhino and I'm beat.