I try to work on one at a time, but right now I have one to bind, 2 that need to go to the LAQer, and 3 I'm piecing. Oh yes, the pp that I work on when I'm watching tv or traveling. Too many right now! :)

Of course, I have multiple projects going at one time. I have been sewing since I was 10 years old, so I guess that means I have had more than one thing going for like, 35 years!
I have at least 1 quilt in each stage of the process. I am also working on cutting for 3 different postage stamp swaps. This is my hobby (obsession) and I work on whatever I feel like working on. I try not to get myself on deadlines to get things finished - takes the fun out of it for me.
This is what works for me and I am pretty good about finishing things...eventually.

Have a few going but like to try to get one done before starting another one. Like to see the finished project.

I have 4 right now..I always have a large quilt for a grand in progress (have 14 0f them!) I always keep a hand stitch project going for while I wait at doctors or for kids. I work on purses and small projects when I need a break to start gift making, and my string quilt gets a few blocks added as I get a different variety of strings in my stash

Oh, I'm so glad to hear I'm not alone! I have so many projects going I've almost stopped working on them! I have two totally finished quilts, one all sandwiched and ready to quilt, about a dozen 6" Dutchman's Puzzle blocks done, several paper-pieced blocks done and into a closed container, to be added to as boredom dictates, and I'm trying really hard to not start anything else, but a watercolor log cabin keeps calling to me. I'm trying to find my ear plugs! :D

I seriously think I need a maid, even though DH doesn't care one whit if he has clean clothes or the house has dust bunnies. I had to stop everything today and mop floors, run a couple of loads of laundry and cook breakfast and dinner. I'm having trouble finding "me time" this week.

My sewing machine went into the shop again two weeks ago, so I've been using a machine I don't like. I finally just quit after a few days, spent most of my "spare" time on the computer posting here, and waited for my machine to come home. Got it back yesterday and now I have to make DH go away long enough for me to gather my own thoughts instead of his! lol

I like to have multiple projects going. That way if I am getting bored with one and need a break, there is something else I can do. I have 3 projects going on right now. A quilt top that is ready for me to get the backing pieced, then it's ready for basting and FMQing. I also have blocks cut out for another lap quilt. And I started working on a tote tonight.

I don't think I would have more than 3 or 4 projects going at the same time though. One thing I don't want are UFO's, and so far I have avoided that. So I like the variety, but it needs to be manageable. :-)

I have 4 active projects going right now. One is a bargello in purples that is 1/4 sewn together. I have a quilt that I designed myself that I'm anxious to get back to. I'm spending most of my time on a wedding quilt that I'm making for a customer...it's a queen. Then there's the graduation quilt for my oldest granddaughter that is cut out, waiting to be sewn together. The last two paragraphs from Helen S. fit me to a "T" except for the sewing machine problem. I had to clean the bathrooms and vacuum today, then get food ready for a church dinner. DH will be busy rounding up cattle tomorrow, so maybe I'll get something done in my sewing shed!

I can't count how many projects I have going. Between crochet and quilting I have too many to count.

When I started out quilting about 3 years ago I wouldn't start a new top until I finished the one I was working on. But, that didn't last long. Now I have numerous ones in the works. I have English Paper Piecing for traveling, a quilt that needs applique on the borders (hand work at night) and several tops in the making. If I get bored with one, I go to another. I found my work turns out better now since I'm not hurrying to get the current quilt done so I can move on. Now I have choices to fit my mood and love it!

That's how I am. I like to finish one before I move on to the next one (ADHD, anyone? LOL!). But I guess it depends on what you mean by "going on". I have numerous in the planning stage (in my mind), a bunch of fabric bought with a very loose idea as to what I'll do with it, one at the LA'er, one waiting for a back & two waiting for borders. OK... it looks like I lied. I do have several things going on at once. But only one that I'm actively working on at one time (like laying on my ironing board active).