Pleated pillows with envelope style backs so they can be removed for washing. They are white, after all. And don't mind the mediocre pictures. Low light, sloppy photographing, un-ironed pillowcases and general vacation laziness all played a part.
This is one of those projects that look complicated but aren't really hard to make. I bought inexpensive broadcloth from Joann's on sale for around $2/yard. I used a disappearing ink pen and drew lines on the fabric two inches apart (this measurement can change depending on what look you want. I went with two inches because that's how wide my ruler is, so it made marking the lines really easy.) I folded along the lines, going all in the same direction, then tacked the edges down. Then I cut the fabric down to the size of the pillow form. Next I made the envelope back (tutorial) and sewed the two sides together. Easy! Thirty minutes of work saved me about $20 for each pillow. Totally worth it!