I once bought a pizza with 10,000 btc. 
yeah i have heard something that there was a person who bough a pizza for that much coins, it must have been a huge loss for him i would have gone crazy if this happened to mei have never made any bigger mistakes with bitcoin to be honest so i dont have any big losses in my carer, i think the biggest one was when i lost like nearly a bitcoin on gambling
It was not a big loss for him at that time. The 10k bitcoins were worth less than $50 at that time as far as I remember.
Of course... the buyer did not think that these bitcoins would be worth $4,530,000 nowadays.