Here is a quick and inexpensive (bar one element) Halloween costume I made last year. I’ve seen some quirky costumes, and I especially liked ones that are unconvential, ones that are of things that seem impossible to replicate in costume form, e.g. board games, websites. I went out on Halloween dressed as Youtube.
I screenshot a Youtube site, and then printed it out across six A4 pages. I stuck these pages together on a piece of foam board, creating one image. I then strung the board to another piece of foam board to make it wearable.
The key element was cutting out a square from the screen area and putting my Android tablet in behind it and sealing it there with duct tape. It meant my costume was actually Youtube, I could play any Youtube video. I actually just put Wrecking Ball on repeat for the whole night, but the costume got a great reaction even though it was relatively simple.
I realise the presence o the tablet doesn’t make the costume particularly cheap, but if you do have a tablet/iPad/phablet, it can be a great addition to the costume.