What has surprised me is that as retail investors, a number of people are actively using exchange rate movements as a means of investment, either in the form of direct buying/selling of currencies or through products such as foreign currency linked structured deposits.
Up to now i haven't been actively considering fx as a means of investment, other than looking to opportunistically exchange money when rates move in my favour. This is mainly because i don't want to get stuck on the wrong side of a transaction with a currency that i don't want or need. However, to the extent i'm indifferent between holding two currencies, there's no real reason why i shouldn't apply the basic investing rules of looking for value & buying low and selling high to the fx markets.
I don't anticipate this to be a significant part of my portfolio, but where opportunities arise i might look to take small fx positions from within my cash buffer.