Seed Trays

I like the look of the Charles Dowding trays but the cells are too small for my liking, makes them harder to keep watered and if the plants get too big the leaves are a pain to untangle. Also I like planting in multiples of 4 (due to square foot gardening) so odd numbered trays would annoy me a bit. Most of the time I use 24 cell trays and they are ideal for many things, but I also like 12s and sometimes 9s. If they made sturdy trays in these sizes I would snap them up. My local gardening centre sells second hand trays for very cheap, though they are usually 4s or 6s which we already have a lot of. I use trays even if they're a bit broken (free air pruning, right? ), they get patched up with duct tape and only go in the bin when they've well and truly had it.

Likewise TMTT - I keep them going for ever with insulating tape. Once one of the modules has definitely had it, I carefully cut that one out using sharp secateurs. 
It makes it even more of a jigsaw to fit the odd shapes on the greenhouse bench though, Scarlet!

When I have two identical but damaged modules I sit one inside the other, with the broken ones sat inside a good one.