Hello. I am a parent of a seven year old bipolar child (boy) whom we adopted at birth. He was diagnosed with bipolar disorder just before his sixth birthday. He exhibited some other strange behaviors but also mood swings and problems with NO. Please consult a behavioral specialist if you feel you can't handle it alone. Not saying your child needs medication--by all means try everything else first. There is an excellent book called Parenting the Defiant Child by Dr. Kadzin at Yale University, which we have found helpful. Good luck.
So, you have discovered that negative attention doesn't work well as a discipline method! Stop taking things away from him!
If you want him to do the right thing, positive attention is the way to go. When he does the right thing, reward, reward, reward. I don't mean stuff him full of candy, but it takes a surprisingly short time for a child who is told how happy it makes you feel when he comes in first time you call, how pleased you are at how patient he is being etc etc. for them to get the message that it feels really good to be basking in the glow of parental adoration. It always, always feels better to be given a pat on the back for doing the right thing than a bawling at for doing wrong. Children are hardwired to want positive attention, but they'll take the negative attention if that is all that comes their way. You have a kid you say is an angel most of the time, so you just have to polish the rough edges a bit!