Tracey Mallett is a big influence on my class choreography. I love her barre and pilates workouts - whether 10 minute YouTube options or full DVDs.
She's challenging but just when you are thinking she must be crazy, this isn't POSSIBLE, she introduces a new move and you carry on!
Here is a ten minute option from PopSugar, which offers great fitness content. All you need is a chair that you can hold at hip-height for balance. Choose an even, non-slip surface to work on.