Well, I don't know about anyone else, but after buying about 12 rocket boosters it is plain to see that there are some practically and simply awesome cards waiting to be transfused into almost every deck.  Here is a list of them my friend.  Read and enjoy...
 
Combos...
Dark Dragonair+Challenge-ok, let's think about this for a minute.  If we play Challenge and fill up our bench (1 of the benched being dratini) and then we evolve to dragonair, then every turn we can choose 1 evolutionary card and put it on one of those guys.  Or better yet, why don't we just get 2 of em' out there.  Then we could get all the cards we needed in 2 turns, and spend the rest beefing up.  The Dark Dragonair obviously has a weakness in the hp area, and that they can't attack very well at all, but this is besides the point.  They are a bench pokemon, and they work well with slam, and if you would like, maybe Dark Dragonite, with that once in a lifetime deal for getting two basic, then deevolve I guess... hmmm????
 
Dark Machamp+Gust of Wind-Just beef up your Machamp and then gust out the heavy hitters and put em' back in the opponents deck, leaving the rest as easy fodder for your pokemon. Can anyone shed a tear for raindance, who loves his little blastoise so much, nope.  But watch out for his lower hp than most.  It seems very unreliable, he would also go well with a switch (laugh...). 
 
Rainbow Energy+Potion-well, by itself this energy isn't really all that great, I mean, take 10 to get one energy of any type?? Maybe on lugia this might be usefull, but I don't really see it being very helpful in most decks, except potpurri.  Well, assuming you need a couple of these guys, a potion would wisk all that damage away.  Or better yet, how about a potion energy??
 
Full heal energy+Gloom-Gloom has long been known to do some kick butt status effects and damage, but he always has one downside.  He confuses himself, or paralyzes or poisons himself.  The same goes to vileploom with his pedal dance, that does good damage but leaves him muy confused in the mucho grande battle field.  It can be very disparaging to see all those lovely numbers and status effects until you read the fine print.  But full heal energy can take all that away in one turn.  Play it on that confused pokemon to totally wisk away that confusion, poison, sleep, and paralysis.
 
Dark Wartortle+Defender (or other defense mechanisms)-this guy doesn't have a great first attack, but reflect shell is great.  Just gust out a full charged charizard and add a couple of plus power or defender, to allow a pokemons over-spending with damage to backfire.  But even without the plus power, charizard would take 200 because of his weakness.  Gust out the charizard and watch them wimper as they either Kamikaze into you like a flaming fighter pilot, or they waste precious energy retreating for a weaker pokemon who will still not evade the glorious attack.  Every pokemon is now a kamakaze warrior, and trainers hate kamikazes. Everyone will think twice about over-killing this dude.  The fact is that people will definitely start playing defender and using mr. mime, because he is the only one coming out alive.
 
Dark Blastoise+Normal Blastoise-Ok, the new rain-heroe, he can dish 70 per turn, no side effects for 4 energy.  Ok, this is awesome by itself, but doing it on the first turn and with no backside, awesome.  Add in a plus power to kill just about anything.  Dark blastoise by himself can kill:All fire, scyther, promo mewto, mew, most of the base and jungle set.  I mean, there are about 5 pokemon in the first 3 sets who could come out after 1 turn with this bad boy alive.  Add a plus power or two and you see even fewer that will survive his turbulent wave of destruction.  And, for those he can't kill, rocket tackle let's you take ten, flip, and scrunch basically.  This does require a flip, and he does have pretty low hp, but he is just plain awesome.  Heck! He can ko himself in one turn!!  He definitely get's my award for the best all around card.
 
Those are all the combos...
 
most of the dark pokemon are worth putting in a deck, but the downside to having awesome attacks and effects is that most have lower hp.  I think that almost all the dark evolutions will start showing up in good decks.  Good luck to everyone out there using rocket cards.
 
-Sean