I had a simple formula:

"I feel like I am contributing at least $X value to the company. If I am then it makes sense to pay me that, and if not I'd like to know how we can get there."

It starts a discussion and it's more honest: if I am not worth that much then tell me how I can be more valuable.

I have had a pay rise every year from this conversation but my company is very flexible and successful, so mileage may vary.

I find all other approaches to me gimmicky and tricks, and somewhat dishonest in some way.