Baby Carrier That Is Not a Car Seat.

The only thing I can think of is an infant seat. Some are fancyier than others but a small simple version might be what your looking for. Another thing to carry though (we are already pack mules):)
B. O
The MOM Team

use a stroller. I had 2 under 2 years and it worked great!

We never used those car seat carriers and only used a sling! It's best for your babe to hear your heartbeat and feel secure near your body! We had one of those really portable bouncy seats for those few occasions when you will put your baby down (as there was almost always a willing hand or 2 with relatives!) Best of luck!

I have a phil and ted's stroller. They have an item called a cocoon that fits into the stroller, but can be carried with handles. The baby sleeps flat in it, and you can put a blanket in there to support her. I've been using it without my stroller. It's $ 59.00. I like it a lot. I have a 5 week old. She likes to sleep in it. You can go to their website and look at it.

You can use a stroller that can lay flat or has different positions. I wouldn't put my baby on the floor (with a blanket) unless it is at home. Then you can use it for several occasions. It worked for us. Sometimes I carry her in a regular carrier if I know that we are just walking somewhere and don't need to lay down like in a doctor's office. Good luck.

Hmmm. My best idea is to use your sling or a mei tai carrier like a Babyhawk to lay her on on the floor, or just lay her on a blanket. My baby is six months old now and prefers rolling on a blanket to sitting in his car seat now, anyway, so I feel like I'm lugging a car seat for no reason.
My sister-in-law had an awesome baby backpack that stood up and her baby could sit in it. It was excellent for hiking but might be a bit cumbersome for the doctor's office and other errands. Some kind of folding bouncy seat would also serve the purpose but might be cumbersome. As she gets bigger (like five or six months of age) you could use a Bumbo-type seat, which wouldn't be too big to carry around. You'll have to look at those and decide if you think they are developmentally appropriate--I know some people love them, but I've never had one, personally. Maybe some kind of moses basket would serve your purpose? Do an eBay search on "moses basket" and see if you like what you see.
Good for you for keeping your baby close--I think car seats are for cars.
Good luck!

Maybe you could take a stroller with you so she could sit in that.

I'd say laying her down on a blanket would be the best thing - not a lot to carry in. You could even use your sling as a "blanket."

I just put a blanket on the floor. The best is a quilt/blanket that's a solid color on the underside and a pattern on the top. That way you can always put the clean side up.

Why not a stroller for those occasions? That way, you can still pick he up and hold her during the times you don't need her to be set down. And you don't actually have to "carry" her in and out with it. You'll probably have a little compartment to carry YOUR stuff! If you're worried about her being so small and supporting her neck or whatever, you can get one of the ones that lays down into a bassinette style. There are tons of options for big or small, compact or whatever. Good luck figuring out something.