DIY tools:

Heating:

Solar Water Lense, used for smelting and heating
(https://www.youtube.com/watch?v=eeSyHgO5fmQ)

Very cheap Solar Grill:

https://www.youtube.com/watch?v=8DG9g3oZuEo

Solar Oven:

https://www.youtube.com/watch?v=mzoL-Rjjg6A

Earthen Oven
https://www.youtube.com/watch?v=i0foHjPVbP4

Freezing and cooling:
https://www.youtube.com/watch?v=hRYuUqYI3nM
Windcatcher and night sky cooling
https://www.youtube.com/watch?v=O10i-Lyujps
night sky cooling
https://www.hobbyfarms.com/cool-your-root-cellar-summer-winter-ice/ winter ice cooling
https://www.youtube.com/watch?v=oHyHwurEefs
winter ice storage
https://www.youtube.com/watch?v=tnJms_3Gbuk
ancient winter ice

Bike Powered appliances:

https://www.youtube.com/watch?v=BoesgorKM_0 blender
https://www.youtube.com/watch?v=MGemYXOGXJs washing machine
https://www.youtube.com/watch?v=CKDTbwsuWQk water pump

Diy washing machine:
https://www.youtube.com/watch?v=o165Py4Ar1s from buckets
https://www.youtube.com/watch?v=KJEGV0LZk7Y wood washing machine

Washing boards:
https://www.youtube.com/watch?v=_bcwq9_OLIA from wood
https://www.youtube.com/watch?v=_4N96YtXFMY wood and metal

Crafting:

DIY cord and pump drills:

https://www.youtube.com/watch?v=ZEl-Y1NvBVI using stone drill

https://www.youtube.com/watch?v=YqRApOOAVlQ using metal drill bits

https://www.youtube.com/watch?v=ZRZ6mzLBSGw using metal drill bits

Misc Hacks:

https://www.youtube.com/watch?v=6och7-0iI00&t=461s

https://www.youtube.com/watch?v=6jn_b1BX51c

https://www.youtube.com/watch?v=pQT9oTUHEo8