Can I join two Super Boomerangs together to get an 8 pointed Ultra Mega Super Boomerang??
Answer: You can join two Super Boomerangs together to get an 8 pointed boomerang, but it doesn't fly as well in my opinion. It gets a little too heavy and will bend much more easily-- but try it out if you want. I would use tape because you can take it off easily if you don't like it :-)
Can I use something other than tape, like glue, staples, etc.?
Answer: Yes, any adhesive would really work. I have found that tape works very well (if not the best) because it creates a nice seal at the areas where you are joining them. Glue would work nicely as well, however you just wouldn't be able to take the boomerangs apart again without ripping them. Staples can work as well.