I had an idea for a little feature a while back and it stuck around in my head so it tends to mean it is not completely pointless. Anyway I like learning new skills and generally if I have needed something done I will set about learning it myself, it might take five times as long, end up a bit wonkier, cost more and see me break a lot of things along the way but in the end I will have a new skill and I like that. GBAtemp seems to feature a lot of people with some interesting skillsets and I reckon getting some people to share "enough to be dangerous" levels of knowledge would be a good thing. Densetsu has his Japanese teaching thread, the writers guild does a fair bit of this and I did have something for video http://gbatemp.net/threads/be-a-great-video-maker-and-replicate-this-video-effect.360509/ For the computing ones I would suggest you try to use open source or good free software. Naturally with some of those that might be a tiny bit harder, especially if you are more used to the commercial ones, but try anyway and you might even learn something yourself. Examples might be Image editing. http://www.gimp.org/ , http://photofiltre.free.fr/frames_en.htm and http://www.getpaint.net/ . Also http://ufraw.sourceforge.net/ I guess before I get pounced upon. Teach layers, masks, selections, gradients, guides, blends and basic theory and you can do well. http://www.inkscape.org/en/ might also be worth a quick mention. CAD and 3d modelling. http://www.beyondmech.com/pro-e/cad-topic-33.html and http://opensourceecology.org/wiki/CAD_tools though I should not inventor fusion still has a nice free version which they both skim over. I guess you could also go more general 3d modelling and include Blender. Though I have spend the last several months bringing up my skills in it. Though layers and the concept of selections frustrate many less experience image editors I usually find CAD stuff utterly impenetrable to one not already brought into the fold. Electronics repair and theory. Even if you teach someone about capacitors, switches and internal fuses you can probably get a lot done. Electronics CAD and all those nice programmable devices are good to know too. However having witnessed the carnage of the early Wii era where mod chips were a thing I might suggest caution. Video editing. Give or take some of the high end after effects stuff I would not be so quick to dismiss the open source video editing world these days, though somewhat amusingly a lot of it has gone Linux only (Kdenlive and openshot both do things I have no free/open source GUI program for on windows). I tend to go more for the technical side of video as that is what I like, some more or that and more of cinematography and storytelling would be well worth it though. Audio editing. http://audacity.sourceforge.net/ and http://openmpt.org/ are great toys to play with. Woodwork. Watch something like New Yankee Workshop (I could probably finish the sentence there and be happy) and you would be forgiven for thinking woodwork was all about very expensive and large tools. You can do a lot with some saws, chisels, a drill and clamps though. I would have gone metalwork as well but that does tend to take proper tools. Desktop publishing. http://www.lyx.org/ and http://www.scribus.net/canvas/Scribus Perhaps not as cool as some of the other things mentioned but some basic desktop publishing is well worth knowing. Cooking. Putting something in the oven is not cooking. Knowing what to do when you put too much salt in something or how to substitute ingredients is. My leanings are far more towards practical things but if you have a skill you reckon you could teach then I am all ears. I know there is already lots for all of those, lots plus one is not going to hurt anything though.