Steak topping i can make

crying tiger sauce, good on tritip, sirloin, and ribeye
https://eggheadforum.com/discussion/903154/crying-tiger-roast

this is really simple, maybe not what you're looking for, but often with a strip or other steak that doesn't have as much richness to it, I'll just mix fresh ground pepper and a little salt into some good quality olive oil and use it as dipping sauce - kind of like you get in some italian restaurants for bread, but with less stuff.  the flavor of a good olive oil in this case is fantastic, really adds richness to the steak.

I usually prefer just steak as is, without a sauce, but once in a while, for a change, I really like this:

Steak with Herb Sauce (bistecca Con Salsa Delle Erbe), from Saveur

They said, "A thick, well-marbled cut—a rib eye, strip, or porterhouse—works best for this olive oil– and herb-topped steak. The dish is based on one served by the Italian-born chef Cesare Casella at Salumeria Rosi in New York City."

1 cup packed basil leaves 
1 cup packed flat-leaf parsley leaves 
2 tablespoons packed fresh oregano leaves 
1 tablespoon packed fresh rosemary leaves 
1 tablespoon packed fresh thyme leaves 
1 tablespoon packed fresh tarragon leaves 
2 cloves garlic minced 
3⁄ 4 cup extra-virgin olive oil plus 2 tbsp.  
Kosher salt and freshly ground black pepper to taste 

Put the herbs and garlic on a cutting board and finely chop together with a large knife. Transfer herb mixture to a small bowl and stir in 3/4 cup oil. Season herb sauce with salt and pepper, cover with plastic wrap, and set aside for at least 1 hour to let the flavors meld.

Bernaise or Hollandaise sauce are not very hard. You can do them in a blender pretty easily. For Hollandaise just clarify some butter (heat butter until just boiling skim off foam and pour off liquid leaving solids in pan). Drop a few egg yolks in the blender with some lemon juice and cayenne and whir while drizzling hot butter in.

I normally just sauté some mushrooms and onions and add a little flour.  Pretty much what @thatgrimguy said.  Sometime I add wine. 

A favorite of mine is a mixture of Gorgonzola/shaved Parmesan. About 50/50 or so and add some horseradish to it. Mix it up good and broil it on. Freakin awesome!

This will kick it up a notch or two.

http://www.greeneggers.com/index.php?option=com_simpleboard&func=view&id=1103259&catid=1

Eggsalent said:

Cookinbob do you just blend them together

Yes. Softened butter(room temp) and the spices. Spread on the steak when you serve. Report back if you do it

Seriously, its more about the steak!  You can do veal reduction sauces, bernaises…  Buy really good steak and do a simple compound butter finish.  Add Tarragon ala bernaise, basil if you like that note, thyme, garlic…  The options are endless and taste profile specific.  Have fun and eat well!