What to do with old hats?

Futurebound

Hi,

 

So I tidied up my kit after the first year of competing in triathlons and open water events and found I have accumulated a large number of hats obviously handed out to denote wave or distance at a given event. 

I have pulled out two good ones to use for training but the rest are of poor quality and I don't need them. I have scoured the internet for uses but so far none have surfaced. I would hate to just chuck them out as none of them have more than about 2km swum in them, so I wondered does anyone have any innovative uses? I read somewhere that latex or silicone are not recyclable so is the only option to chuck them out?