I use the heart-shaped cans from valentine chocolates for small size spools of thread. The lids fit snugly, and DH is more than happy to buy them (and helpfully eat most of the contents). I use scotch removable tape all the time when placing a small piece on top of a larger one (where a pin would distort things) or to place applique pieces. Lately, I've been using a frustrating,,stretchy fabric, and at times i've had to tape the block to my table to keep it square while I set the sashing strips on top. It doesn't stick as much as painter's tape, so it's useful for tricky applications.
Hugs,
Charlotte