Oddly, they're kind of pleasant. Sure it feels like all of the air is being crushed from my lungs, but there is something cathartic in such total expulsion. I can almost understand why people in the past worried that a person's soul might get expelled through such a process, inviting evil spirits to inhabit the body (thus requiring a "bless you" to protect the body until the person's soul finds its way back).
For me, the moment I feel a sneeze coming on, I try to force the issue by looking into the brightest light that I can find. I don't know why sneezing is photoreactive, but the trick usually works. When it doesn't, I feel unsatisfied and incomplete.
In the end, I look forward to these sneezes, even if I hope that they are not harbingers of an actual illness.