This is a step beyond the WTW 4 letter sound sort. I took it back a step, and made sorts of only 2 letter sounds each. Follows the same sort order, just a 2-sound sort, instead of all 4 at once.
BMRS - MB, RS, BR, SR
TGNP - TG, NP, TN, GP
CHFD - CH, FD, CH, HF
LKJW - LK, JW, LJ
Also includes a letter-sound clip art image similar to letter factory.