Charlie: A couple that I can think of right quick...using cynoacralate glue to hold hardware together while inserting in awkward locations...using it again to glue nuts and washers to sockets or wrenches for the same reason....drilling out steel/CRES/Ti hardware when heads are too messed up to use normal tools...using a compass/finger to lay out lines parallel to edges whether curved or straight....safety wire to hold Adel clamps tight when you need to remove the bolt but don't want to let the clamp get loose...using double face tape to hold parts together while piloting holes.

Coming from an aircraft production background, there are lots more out there that would help builders along with some tool usage tips too. A couple of those might not make sense to you, so PM me for a better explanation.