I have read on many Emergency Bag lists that sewing needles and thread should be added, usually a small boxed sewing kit. Well, I did find something that I think would be a good addition to a bag. Well I found a really nice sewing awl stitcher kit called 'Awl for All'.
It comes with the stitcher, instructions, two needles, a spool of really thick waxed thread, and a screwdriver tool. It is really light and compact with the needles and screwdriver all fit in the hollow wooden handle with room for extras if you need it. It works really well on sewing up thick leather and supposedly canvas. The most it does is a lock stitch, but for making repairs or needing to just sew things together, it works really nicely. I have been practicing on really thick leather. It is something I would add to a bag or just use every day. I picked it up for about $11 at Sportsman's Guide . They do have a deluxe kit, with the stitcher with some large spools of thread and extra needles outside what the original kit has.
This is what it looks like all together with some practice stitches.
CORRECTION: I added in the word 'supposedly' when mentioning it works well with leather and canvas. I have not worked with it on canvas... yet. I will try it though. Sorry about that. Also, there is a main website Awl for All for the little awl. It says it can be used on tarp, plastic and sail material. Thought I would add that.