I often look at the work of other painters to learn new techniques- and online there are hundreds of tutorials for every level of painter to be found.
Once upon a time, I was most excited about tutorials that would give me strong color recipes. I wanted to make my minis look exactly like the ones pictured, and I was often upset if I didn't have the same paint pots that the painter had used.
Nowdays, I'm a little of the opposite. I like to take a technique and try to push it a little farther, and press it a little harder until I find uses for it that I hadn't thought of before.
Here's an example. You can take the same Lightning Effect that I've used on power weapons and such, and alter it a little to make a cracked earth lava effect.
The big difference between the lightning and lava is the pattern. Lightning needs to fork outward, so you always have a definite direction for it to be traveling. The lava, on the other hand, simply needs to make shapes and connect with other strips of lava.
Oh, and the colors are different too.