What Tom said except I work for Amazon. If we aren't including that then there are a few things I do on the side or used to do to make what I call "Fuck It" money.
1.) Usertesting. Testing out programs/websites while recording my reaction to the site as well as my thoughts on it's infrastructure, features, color scheme, etc. Typically recordings were around 5 minutes long and paid me $10 each.
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2.) Video game beta testing. Testing out new DLC/AAA games before they hit the market. Most of the time it's just me and 30+ other people testing out the multiplayer servers. (Does voice work? Matchmaking? Any glitches?) Tests usually last 2-3 hours so a nice $20-$30 per session for playing video games? Hell yeah.
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3.) CSGO match betting. Placing bets on CSGO matches with CSGO skins. I originally started out with $200 in skins and placed quite a few bets. Made over $1K and then cashed everything out. It was fun playing competitive/casuals to see how triggered people got when they saw my $900 Dragon Lore and $598 butterfly knife though.
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