From Minecraft Wiki
This is a list of 8px or less texture packs. There are very few textures so far, but as time goes on, we hope more will be added.
Note: Please click on the images to gain a better view.
|Low Resolution Texture Packs|
|Name||Description||Author||Texture Size||Version||Link||Latest Compatible Release||Size|
|EightPack||A low resolution texture pack for the retro-extreme pixel artist or the geek with the inferior computer!||UltimateRecursion||8 px||v1.6||Planet Minecraft||1.6||1,115 KB|
|LD Faithful/PixelPack||One of the only 8px textures that isn't just simplified — but also retextured.||Stronghold257, Joe4429||8 px||v1.4||Forum PlanetMinecraft||1.4||977 KB|
|T4S Pack||Checkered grass to suit your needs — and also cute 4px blocks!||tynnoel99||4 px||Planet Minecraft||1.4.7||1.24 MB|
|OneCraft||One pixel blocks! Especially useful if you're tired of HD textures.||TheLarsinator||1 px||Planet Minecraft||1.6.2||3.89 KB|