It all depends on what you consider a splurge. I switched to a NeoAir, which meant, for the first time, my weight went up (I was switching from a closed cell pad). For many, they had already made the switch to some sort of inflatable (for comfort reasons) so switching to the NeoAir was actually a drop in weight. I'm sure I have plenty of things that people consider luxury items. If you use a tarp, then even a tarptent is a splurge.
But the first thing that pops into mind is my camera. I really don't need it, nor does it help me sleep any better. It doesn't weight that much, but with the extra batteries and foam case, it probably weighs about a half pound (I'm not talking about a "real" camera, just a compact). A half pound isn't much, except that I would be hard pressed to think of any other way of easily dropping a half pound. Still, I imagine I will stick with it; it is really nice to show people what a place looks like, and not just try and describe it.