I travel for business all the time. You can take scissors up to 4" long - even sharp ones. You can take crochet, knitting needles (I generally use short ones or circulars on the plane so I won't stab anyone but you can take any kind of knitting needle.) I frequently take a small breath mint (alto kind) box with small embroidery scissors, thimble, needles and a spool of thread. Then any hand piecing or handwork I have to do...I even point it out to the security and they say it is fine.
So - no big scissors, but otherwise just have fun!