I've never really found an instant coffee that tastes great. The quickest method I've found is the
Aeropress. Heat up the water, grind the coffee, pour, stir, press, go. I can't imagine it's too much slower than instant, and much faster than brewing a whole drip pot or french press.
They were giving away Starbucks Via in the lobby of my office building a couple of months ago. I'm surprised to agree with their advertising - it tastes remarkably like their drip coffee. Sadly, that's not much of an endorsement.