This page contains dishcloths made on the diagonal. Unless otherwise noted they are knitted.
More Diagonally made cloths can be found here.
8 inch Garter Stitch Bias Square-about 1/4 of the way down. Not designed for a dishcloth, but makes a very good easy one when made with cotton yarn.
Corner to Corner Dishcloth-( C )
Diagonal Cloth With Scallop Edge-( C )
Diagonal Dishcloth of Summer-( C )
Diagonal Stripes Dishcloth-( C )
Diamond Dishcloth-( C )
Eyeletless Diagonal Garter Cloth
Multidirectional Diagonal Dishcloth

Thanks for that first link. I’d never seen that blog before. When I get a free moment (hehe) I’ll enjoy perusing it to find something interesting to make.
Thanks for the concise list of dishcloth pattern links. I can’t believe that there is a website all about knitting dishcloths. That’s pretty cool.