Sorry Duk, but this equation will always be true:
$$$ = Speed
The 'value for money' part does depend heavily on the car, and how many people have done work to armortize the cost across the market. Sadly, the Alfa 75 isn't a 200SX or an AE86, or a Type-R. But you already knew that
Lots of good tips above, but they will all require you to open up that wallet, or swallow a little pride and 'hide behind lower diff ratios'