Anyone who spends any amount of time reading what I write will notice something rather quickly. I am severely dyslexic. I transpose letters, and I transpose finger positions on the keyboard, so you might see a u where an I or a Y are supposed to be etc...
I don't even notice this most of the time, and I tend to write a lot of technical stuff, with abbreviations and acronyms etc... so spellchecking doesnt help me all that much. It's jsut something that I live with, and when I notice, I correct it.