Given the limited amount of practice time we have, we have to find a way to get in top condition while getting enough work on our skills to improve and be ready to play against top competition. The traditional ways of conditioning, running sprints, distance, etc., are very effective as conditioners but have no relevance to the game. Running suicides or 17's (running sideline to sideline 17 times in a minute) might be a little more game like (very little) but still does nothing to improve your skills. Below are some ideas where you can accomplish both better conditioning and better skills.
Full Court Dribble
Start at the baseline with a ball. Using your right hand, dribble to the opposite baseline with 5 dribbles. Switch hands on the way back. Next try it with 4 dribbles, then 3 dribbles. If you do them all in a row, you have run 6 sprints. Put a lay-up on the end of each sprint and you have worked on your conditioning, dribbling and layups all at the same time. You have improved your ability to score on the break and in transition.
Start at the baseline. When ready sprint to mid-court. Upon reaching mid-court, get in your defensive stance and defensive slide, diagonally, back to the baseline. Change direction twice. When you reach the baseline, sprint immediately to the foul line. Upon reaching the foul line, get in your defensive stance and defensive slide side to side. Change directions twice. After the second change in direction, sprint to the far end of the court and touch the rim 10 times. Take a minute to rest. Step back up to the baseline to go again. This time, change directions 4 times. On the next set, change direction 6 times and then 8 times in your last set. You have increased your conditioning, improved your defensive footwork and worked on your jumping.
Beat The Pro
Pick your favorite player as your imaginary opponent. In this case we'll use Kobe Bryant and your opponent. Start with the ball on the baseline. Dribble to the foul line and shoot a jump shot. Then, chase down the rebound. If you have missed, score the rebound by making a lay-up. Then dribble back to the foul line and shoot again. Keep score. You get 1 point for every jump shot you make (rebound layups don't count) and Kobe Bryant gets 2 points for every shot you miss. Play for 2 minutes. If you win, take some foul shots. If Kobe Bryant wins, do the full court dribble drill (see above) 1 time for every point he beat you by. You have worked on your conditioning, ballhandling, shooting, rebounding and layups.
Pick 10 spots, 5 on each side of the court, that you think you can shoot effectively from. Start with the ball under the basket. Spin out to the first spot (a spin out is a toss with bask-spin on the ball. Done properly, the ball will hit the ground, bounce straight up and "wait for you"). Sprint after the ball, catch, make a right foot pivot and shoot. Chase down the rebound and if it was a missed shot, score with a lay-up. Grab the ball out of the net and immediately spin out to the second spot, then the third, fourth, etc. Continue until you shoot from the 10th spot. After the 10th spot, reverse the order (spot 10 becomes spot 1) and go back the other way, using left foot pivots. Continue using different pivots on each rotation. Your objectives are: make as many 1st shots as you can, make 6 rotations (60 shots) in 10 minutes. After your 6 rotations, relax by making 15 foul shots and then start again. The drill can be done with any pivot, practicing jump shots and 1 dribble moves. You have worked on your conditioning, shooting, rebounding, follow shots and pivots.
Using these drills together would make a great workout. Not only will you be in better condition, but you will be a better player.