Some of these sewing hacks are pretty nifty. I particularly like No 21 (to prevent button hole butchery), No 22 which I desperately need, and No 17*:
28 Sewing Hacks That Will Change Your Life
When considering tip No 2, I would strongly advise to keep magnets away from your PC, laptop and other electronic devices: you don't want to wipe them.
*: You can squeeze a third pencil in between these two to get a wider seam allowance.
Do you know of more tips like these? Have you tried any tips and hacks like these and how did they work for you?