I was one of those adventuresome moms who actually wanted to try tandem nursing, which is nursing a newborn and toddler at the same time.
I had that opportunity when my fourth child was born. I had stopped nursing my daughter in January, just a month before my son was born and when he was born she still showed an interest in tandem nursing. At that time (2002) there was barely anything in the breastfeeding books or online. That's when I turned to going to some La Leche League meetings for support because it was almost taboo to be nursing a toddler, let alone two children at once. That daughter nursed for 2.5 years, until my son was 6 months old and I got pregnant with our fifth.
Tandem nursing is one of those experiences in motherhood that I cherish. Yes it may have taken extra time etc. But I believe my sons and daughters are very close friends because of their start with tandem nursing. I remember my daughter reaching across my breast to hold hands with her brother while they nursed together. It was so precious.
I have tandem nursed two sets of children. Both were a son and daughter combination both were a newborn and toddler, in both cases the daughter was the oldest and extended nursed until 2.5-3.5 years old.
If I had the opportunity to tandem nurse again, I would do it.