My favorite interchangeable needles:
I tend to use circular needles for all knitting since you can knit flat and in the round with them. Additionally, I like to have the needles on a 32" or 24" cord since I usually use the magic loop method to adjust it to the size of the piece. I usually buy interchangeable needles but rarely change the cord
Tapestry needles:
I tend to use whatever tapestry needle I can find, but anytime I have the choice, I like to use these ones!