sparkys_mom

You can purchase a gallon of Elmers washable school glue on Amazon for $13.95 - very economical. I refill my glue bottles from the gallon container but I think I'll take a tip from madamekelly in the future for basting - great idea!

Also, for the finer applications like bindings and precise piecing, you can get the micro fine dispenser tips from PurpleDaisiesQuilting.com. They fit right on top of a regular elmer's bottle. I find them indispensable for bindings.

Mdegenhart

I use a tiny fine line of washable school glue to "baste" pieces in a block rather than pinning before sewing. I can chain piece faster without worrying about hitting a pin. The pieces don't slip like pinned ones do and are much more accurate. You do have to let them dry. I run the glue inside the seam allowance, so I'm not sewing through it. I glue baste while watching TV, etc.

Faintly Artistic

The off brand, purchased from a teacher supply store, by the gallon is cheaper and works just as well. I dilute it about 50/50 for sandwiching a quilt. In my experience, it is NO FUN to hand quilt through, so now only glue baste for machine quilting.
For glue basting pieces, I bought the fine tips from Sharon Schamber's website. You can screw them on to the little bottle. I save the small bottle and refill it with the gallon jug. When basting pieces, I don't dilute it. Always iron to set/dry it before sewing.