I once worked for a company where the marketing department sent huge powerpoints presentations to each other via Lotus Notes. All people in the same office sitting next to each other. The Lotus mail server had no real issues with it, but i told them to stop abusing email as a file server and use the shared drive for that purpose. Took some time for them to getting used to, but the shared drive was so much faster for their purpose they quickly adopted to this ‘new way’ of working :)