Because you asked for it. Maybe?
Namco Bandai has announced a HD remastering of Dragon Ball Z Budokai and Dragon Ball Z Budokai 3 (what does that say about Budokai 2, eh?), two PlayStation titles showing that a Dragon Ball fighting game can actually be good.
This is also before the Dragon Ball series believed that a behind-the-shoulder camera for a fighting game was a good idea. As usual, this HD Collection will have full Trophy and Achievements support. No pricing details are available yet, but I suspect that it should be around $30-$40.
Dragon Ball Z Budokai HD Collection will arrive this Winter for Xbox 360 and PS3.
On a related note, I suggest watching the Season 2 Finale of Team Four Star's Dragonball Z Abridged. Or just watch the whole thing, because it's hilarious and amazing.