L.G.
Hi K..
We celebrated our 6 year last year and we too use the "suggested" gift list either traditional or modern.
I went with iron...a old-fashioned cast iron skillet (Army Surplus...less than $15). I went a step further & had it engraved with a special message & the date. The engraving was more expensive than the skillet, but you could limit what you say ;).
Good luck & Congrats on 6 years together!!!