add blot plotter to plotters section

Author: beardicus

README.md

@@ -55,6 +55,7 @@ Pen plotters available to build or purchase, historical information, and restora
 - [EggBot](https://egg-bot.com) - Pen plotter for egg-shaped and spherical objects.
 - [HP Pen Plotters](https://www.hpmuseum.net/exhibit.php?class=4&cat=24) - Vintage desktop and floor-standing pen plotters from the creator of the HPGL standard. Model 7475A is very common and can usually be found on eBay.
 - [Roland Pen Plotters](https://www.youtube.com/watch?v=6_pwzqPk6Gg) - Vintage flatbed HPGL pen plotters. Search eBay for "roland dxy".
+- [Blot](https://blot.hackclub.com) - An open-source DIY pen plotter from Hack Club with a browser-based editor for generative art.
 - [BrachioGraph](https://www.brachiograph.art) - A cheap and simple plotter made from sticks, servos, and a Raspberry Pi running Python. Here's [video of a BrachioGraph talk at PyCon UK](https://www.youtube.com/watch?v=u4Jh1daCl60) from the creator.
 - [Arduino CNC Drawing Machine](https://www.diymachines.co.uk/arduino-cnc-drawing-machine) - A fairly simple 3d-printed AxiDraw-style plotter with good video documentation.
 - [PlotterXY](https://github.com/jamescarruthers/PlotterXY) - A coreXY plotter made from extrusion, 3d-printed parts, and an inexpensive 3d-printer control board.