#1 - First contraction at 4am, he was out at 7:45am, I pushed for maybe 15 minutes. It was natural/spontaneous, after a failed induction a few days previously (and no, I left after the failed induction almost less dilated/effaced than when I went in). No pain medication at that time, although I did have demerol and morphine one time each during failed induction. Unless you include the numbing stuff they used to stitch me up after a second degree episiotomy. This was at a hospital.
#2 - Water broke at 1:40am, he was out at 7:03am after 3 minutes of pushing. It was natural/spontanous, no meds, just skid marks/surface tears. It was a fabulous homebirth. During my labor I was a little pissed because it was taking longer than the first one, but this little guy ended up being 9lb11oz (his big brother was 7lb15oz at birth). We weren't sure if I was having twins or not because I had been measuring so large, but it was only one kiddo.
And fwiw, the homebirth was fabulous because I didn't have to contract along with dh hitting every single pothole on the way to the hospital, and I was perfectly fine laboring in just a tank top (since my water had broken, I just kept a prefold underneath me - pants/underwear didn't last long). Plus I got to curl up in bed next to my new one and nap, which was so very nice.
Oh, and I have a strong maternal history of quick labors... we're just built to grow 'em and birth 'em without many problems.
ETA: I was 40w3d exactly with each of them. So if we get pregnant again, I have a pretty good idea what the exact due date will likely be.