Maintenance/cleaning vids, esp. how to clean the lip of the atty cap. That of course would not be an issue if the Chinese 901 attys I have were not so crappy for dripping. Damn metal ring inside, argh.
A 'GGTS for dummies' type of thing would be great

Systematically going through all of the parts, how they come off and go back together, etc. There's all the info here in this forum of course, but a vid that was like a 'So you've got your GGTS...now what?' would be great.
Production notes: Complete with cheezy infomercial music, or maybe some Yanni, and shots of the GGTS sitting on a rock with ocean waves crashing behind it of course. Or two gorgeous people dressed in gauzy white clothing, barefoot, running through a spring meadow and blissfully leaving thick clouds of vapour in their wake.
ETA: A green screen shot of the GGTS descending from the heavens would also work well, especially if you can swing getting a Jesus lookalike vaping in heaven, and then blowing the vapour down to us mortals, which then forms a 'vapour-road' upon which the GGTS, borne by a golden chariot pulled by winged horses, descends to earth.
These are REALLY good ideas
