I have experimented with m_, s_, just _, and no prefix at all. I have settled on using just _ for all static and instance variables. I don't find it important to distinguish static variables from instance variables. In theory it sounds good, in practice it doesn't create a problem.
A coworker once made a convincing argument to eliminate all prefixes, we tried it on one project and it worked better then I expected. I carried it forward to my next project and became annoyed that it "interferes" with Intellisense. When you have the following situation
int foo;
public int Foo
{
get { return foo; }
}
Starting to type foo will suggest both the instance variable and the property. Prefixing the variable with an underscore eliminates the annoying double suggestion, so I switched back to using just _.
