The Daiwa Figure 8 Tool is one gadget that spin fishermen or baitcasters may want to have handy. Spin fishermen do not need nearly as many gadgets as fly fishermen, but this is a good one. It makes any knot where you have to reach through a loop to grab line on the other side much easier. I use it for the Palomar knot to tie the lure to the line, and for the Surgeons knot I use to tie a clear tippet to my hi-vis spinning line. Sure, there are other knots you could use, like a nonslip loop for the lure to line connection, or a double Uni knot for the tippet to line connection, but these knots work for me.
The Daiwa Figure 8 Tool is dead simple to use. Insert the silver tube through the loop, slide the black button forward, which extends a tiny hook through the tube, hook the line that has to be pulled through the loop and then pull it back through the loop. It takes longer to explain it than to actually do it. For those of us who no longer have the dexterity or eyesight of an 8-year old, this tool is a lifesaver.
The tool isn't cheap at $30, but it is the only tool that I have lost and immediately bought another, without even thinking about it. (Being bright orange helps, but I still managed to lose it).