I've forgotten many things when commuting into work:
Cufflinks
I once knotted short treasury tags and fed them through as cufflinks - not because I'd forgotten mine but because I'd taken double-cuff shirts to the office by mistake.
I got countless compliments for the knotted treasury tags.
Nobody even notices the most gorgeous cufflinks.
There's a lesson for me there, but I'm not sure what it is...
A further thought on cufflinks... If you have a teenage son and are stumbling around before going out one evening, saying "Where did I just put my links?", don't be surprised if your son hands you a black can of some ghastly cologne that smells like a whorehouse and says "Use mine, Dad". Apparently, it will get me laid. Why would I want to bother with all that sweating and groaning at my age? Preposterous!