This idea is not the newest, nor is it the most complicated. But nevertheless, I wanted to do it - and, as it turns out, it was an incredibly good and interesting experience for me.
Here is a half-done, almost-not-working bot for Telegram which will send you new pictures, gifs, and video files. There are probably many bots like this already, and this one is no different. You go in, add as many "subscriptions" to all sorts of tags as you want, and wait for new posts. The only difference between this bot from the rest - it has more or less user-friendly interface and the fact that the bot sends a new picture every 5 seconds (if it finds them). There is nothing else.
Open bot in Telegram
Bot's source code (if someone needs it)
If you have any questions, suggestions, or if you find any bugs, then you can message me (Telegram) and I'll try to figure it out.
I am open to your ideas. Here are some of my current ideas: make a similar bot for Discord, add ability to turn off tags from subscription, add some convenient way to view pools.