Sometimes it's nice to give people a photo of you together (I would recommend this for parents/ other family members, best friends, or significant others), but other times it's really best to keep yourself out of it and should include a favorite place/ scene instead.
Once you have found the right picture you have to decide if you should decide how large you want it printed, what kind of frame you should put it in (definitely keep in mind their current living situation/decor) or if you should print it on canvas (I really love the look of this, but have yet to try it).
Image courtesy of Kelly Ward
You can also get an album printed online with space for captions, make a collage (other online or by physically cutting out the pictures), or turn it into a card. One of my friends even puts pictures together with music and quotes in iMovie and gives it to the person on a CD. Photos can be a relatively easy and meaningful gift to most people on your list.