It's so hard to find something that my husband would like.  It's especially hard to make something for him (other than food) that he finds cool, until I made hims this Space Invaders ornament. 
I have a 
Cricut Mini, but as I said before, its not very useful when you want to cut your own designs.  To cut this space invaders vinyl I printed out 
this image that I found on the internet.  I did multiple sizes because I wasn't sure which one would fit the best.  After finding the best fit I cut out the image and taped it onto a piece of black contact paper.  Then I used and 
exacto knife to hand cut the image (which isn't as hard as it sounds).  You do want to shift the pixels over a little on some of the diagonal pieces so the image is attached on a small corner.
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| Print out image. | 
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| Tape on top of contact paper and cut out. | 
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| Stick on ornament. |