Good scissors are a must! I love Ginghers, 8in dressmakers for regular sewing, 7" bent, 5" craft, 4" embroidery..both straight and curved blades with large finger holes.
I love the Purple Thang! That little plastic thingy is handy.
An Awl is priceless for guiding fabric and helping thick seams through the needle, as well as removing threads.
Just a few I can't live/sew without.