Rack and fender threaded eyelets
How many of you MTBers consider these a vital feature on your frames. Over in touring we are trying to help some guy tourify his Al frame which doesnt have a complete set of eyelets.
Some manufacturers put them on entry and mid-level frames, others dont. Very few high-end frames seem to have them.
In my opinion, they weight very little and add a whole new dimension to your riding possibilities.
When I was shopping for a mtb I made sure I bought something that had eyelets on it. For the style of mountain biking I do a rack doesn't get in the way at all. I don't do much in the way of technical stuff, I ride more for the scenery with frequent stops to take pictures and attempt to I.D. any birds I may see. I have a hydration pack, but I only carry water in there (the less on my back, the better). I usually have a rack bag on where I keep all the vital tools, plus my camera (I never go riding without my camera), binoculars, bird map, snacks, etc.