Are ballasts necessary with CFLs?

I was going to get 1000w high pressure sodium lamps, but I've been having success with my 125w cfl, so I'm leaning that way now. Will I need a ballast with CFLs? I'm planning to run a total of five or six 105-125w lamps. Thx.

actually cfl's come with a built in ballast

-are u using a ballast with your other cfl?

yah, most of the newer cfl bulbs have a built in ballast, that is why they are so big at the base, that is where the ballast is on them..
just a side note though, if you think your having good luck with cfl's, you would be amazed at what you would get with a 1k hps.. the only negative about a 1k hps is the amount of heat that they will put off imho..

i have a pretty big hps that has a ballast kit.. i cant even use it cause i dont have a clue how to wire the ballast.

so ive just been using cfl's also

I'm not using a ballast, so I guess it is built in. Thanks.

HPS just seems a bit expensive because not only will I need the bulbs and reflectors, but I'll also need the ballasts and an air conditioner. I'm sure I can find cheaper ones on the internet (like $200?), but the high quality, digital ballasts at my local grow store are $400 each.

If I'm not mistaken (I'm going to call 1000bulbs.com and ask them a couple of things, tomorrow), I can build a homemade CFL setup for flowering for around $20-40 for 2 plants. This would include five 23w CFLs @ $2 each, mounted on plastic/wood with 2-3 power strips. Plus, adapters for the outlet/male end. The strips and adapters are about a buck each. I'll use two $1 chains to raise and lower the lights.

Am I missing something? : )