Fascinating stuff. I've now done maths for some years now and this is the first time I even hear about sheafs.

Makes one wonder what else you may have missed just because it's not something profs at your programme are interested in.

edit. Follow-up. I wonder if there's a list of curious and possibly useful math stuff you might easily miss because it's not as ubiquitous and 'canonical' as (e.g.) analysis, linear algebra or functional analysis?