I have a side habit. When I run out of ideas for what to build next, I do not open Twitter or Product Hunt. I open Reddit.
There are about thirty subs where the same complaint comes up every week. Someone describes a workflow they hate, asks if a tool exists, and a commenter says "I wish, please tell me if you find one." That second comment is the cofounder you do not need to pay.
Here are 5 I pulled from threads in the last few months. Each one has a real Reddit post behind it, real search volume on the keyword someone would type into Google, and a wedge small enough to build over a weekend.
None of these are billion-dollar ideas. All of them could be a $2k MRR side project if you actually shipped.
1. Invoice reminders for trade contractors
