Tutorials are powerful ways of attracting new visitors and of keeping current visitors coming back.
Often they are fairly long-ish and present great ways of you demonstrating your expertise.
Not only that, but a beginning tutorial on how to do something leads to more advanced tutorials. This brings your visitors back more and gives you yet more chance to demonstrate expertise.
Now, all of that is fine and dandy but here's what is even better about tutorials; they are heavily shared.
In other words, they spread the social media networks fairly quickly. This gives you boosts to your search rankings along with traffic from a growing variety of sources.
What tutorials can you create for your market?