I do make them occasionally, either for gifts or for myself "just for fun". I like 5 x 7 or 6 x 6 inch sizes, and usually I make my own covers out of chipboard and binder rings.
I've made several baby mini albums as gifts this year and a Disney memories book for myself.
I really don't like them, because I don't now what to do with them after, but I have made several of them. Now I DO like the small SN@P albums; I think they are 6 by 8.
I've made a couple and I think one was 3.5x5 and the other was 3x3 maybe. I have full intentions of making a couple of some mini camping trips that we have taken and I want to do them in 6x8 or whatever size I decide to cut the chipboard covers.