I've always been a 'tweaker' maybe it's my upbringing on a ranch and being able to fix anything with a little bailing wire and duct-tape. I'm constantly trying to find a better (err, cheaper) way to do things. Here are 3 of mine.
1) I couldn't find a bore guide to fit my 338 Allen Mag and after leaving several messages at different bore guide mfger's I decided to just make one myself. I cut down a fired case and epoxied a tube into the case. I used the plastic bodies from 20ga shells to make a perfect fit in the action. It holds it tight/straight and works like a charm.
2) I didn't like the 338 jag I was using, as it was too long, when I was cleaning, there was knurling that was not covered by the patch. It would rub/file on the opening of the bore guide if I wasn't really careful. I chucked it up in the drill press and a couple minutes work with a bastard file and I had a jag that was only .338 caliber under the patch and smooth elsewhere. It probably makes little difference, but I like it better
3) Homemade scope level, using a picture frame bubble ($1.29 at the hardware store) and a dab of epoxy turned a Butler Creek scope cap into a very workable level. A small mark on the cap and scope body with a sharpie marker and I can always verify it is level (initially calibrated with the level-level-level). It is thin enough that it does not contact the lens on this scope.
Have a great day,