Ok, if we're talking about *completely random* tips, I'll stick my 2 cents here as well. They are very obvious for some people, but might be useful for beginners I think
1. If you want to create so called "cut-outs" from your pictures, i.e. remove the background completely, tools like "magic wand" work perfectly if there's a high contrast between the subject and the background. However if the background is busy, "magic wand" fails miserably and you end up defining the outline manually - in this case getting even a cheap graphic tablet will make huge difference. Our hands are much better at marking fine details with a pen as opposed to a soap bar (a.k.a mouse).
2. If you want to shoot glass, place the light source behind the subject, not in front as you'd normally do.
3. Silverware looks best on a black, however if for some reason you need to shoot it on a light background, place a sheet of black paper outside the frame: silver will reflect some of it and define the outline much better. Also use a polariser to control the reflections.
4. This one is pretty obvious
calibrate your monitor. Devices like spyder or pantone huey are really cheap now and it does make a difference.
5. This one probably is rather classed as "imho": in situations (macro photography, for instance) where you can choose between a remotely triggered flash and an off camera flash cord, choose the latter. Somehow it results in more precise metering.
Not sure if these are helpful in any way, it's just from my personal experience