Making Quilts from Bags of Squares

I am a scavenger, I admit it.  I make a lot of quilts, and I don't like paying full price for fabric.  Especially when full price is $12.00 a yard!  (I actually bought 2 yards at that price once.  It still makes me feel sick.)
So I look for deals.  I use coupons.  I root through stacks of sale fabrics.  I search online.  I buy vintage fabrics at flea markets and in antique stores and at rummage sales.  "Pre-owned" fabric doesn't bother me at all.
Last year at a local quilt show I scored an amazing, if slightly odd, deal.  The It's A Stitch show always features a booth they call Granny's Attic, which is like a quilter's rummage sale.  They sell fabrics, books, patterns, etc. donated mostly by their members.  I of course went to their booth first (before even glancing at the quilt show.  Shopping is important!).
On the table with the fabrics were several bags of quilt squares.  These were gallon sized bags, stuffed with squares cut from all sorts of print fabrics.  They were priced at $5.00 each.  I snagged 4 of them, for a grand total of $20.00. (I bought a lot of other stuff there, too, of course, but I'm talking about the squares here.)  I especially selected bags with kid fabrics, since I love to make quilts for kids.
When I got them home and went through them, I found them to be mostly rotary cut to 4 in. square.  A few were blends, but most were good cottons.  There were hundreds of these squares.
These were so easy to use for leaders and enders.  Here are some of the quilts I have made from them so far.

Remember this one?  All these squares came from the sale, except for the purple with dots.

The pink and the hearts print in this quilt came from the sale.  I added the light blues.

All the squares in this quilt came from the sale.  I added the solid green from my stash.  It came from a flea market.  This will be a lap robe for a nursing home patient when I get it quilted.

I finished quilting this one last night.  The frogs and the green dot came from the bags I bought.  I added in a second blue and a second green.  It will have a blue binding, maybe later today.

I had to take these Monsters Inc. squares with me to the fabric store to find something to go with them.  I'm making four patches as leaders and enders.

And here's what I still have left!  I divided them into two groups, based mostly on color and print.  The ones in the lunch box are more subdued colors, suitable for nursing homes, etc.  The kid fabrics (including Dora!) are in the pile with the baby fabrics.  I was really not sure where to put the spring fabrics, but I want to use them soon.  We need some flowers around here.
I just have to wonder about the person who used to have these fabrics.  Why did she (probably a she) cut them all into 4 in. squares?  This must have been yards and yards.  It must have taken a long time.  They don't look die cut, like they would if they were sold commercially.
I wonder how many more quilts I can get out of this pile?  Anybody got any good ideas for using squares?  I'm getting a little tired of 4 patch and 9 patch.  Leave me a comment with suggestions, please!

By the way, this is my basement piecing treadle.  The decals say Domestic, but it is definitely the same as a White Rotary, "T-shirt" slide plate and all.  She is a lovely brown color, and a very reliable machine.  I have some trouble with her bobbin winder, so I use a Side Winder gadget and just wind as many bobbins as I can before I start a big job.  No cabinet, but the base was made from a board with a cut out and the White irons.  She's the most portable treadle I have.  Oops, I need to dust!