Macro Reversing Ring
I photographed the lichen growing on this concrete 'mushroom' thing using an 18-70mm zoom lens fitted with a lens reversing ring.
A reversing ring will convert any 'standard' lens into a close up or 'Macro' lens for a fraction of the cost of a dedicated Macro lens.
Fit a reversing ring to a zoom and you have a close up lens with a zoom facility - that's something a proper Macro lens can't do.
To use a reversing ring you have to make a manual exposure because the lenses electronics won't work, and in this video I control depth of field with a blob of Blu-Tak so it's all very low tech but with great results.
Costing from around £5 to £10 compared to a proper Macro which would start at the £250 mark, a macro reversing ring becomes a very cheap alternative. Image quality is as good as the lens you're using it on.
Personally I love low tech solutions to all photography. great images is more about you and how you think than the price of your kit. A lens reversing ring is a great example.