Essential baby supplies
I know this is super early, but it doesn't really have anything to do with me so take it easy when you see I am only 10 weeks pregnant you crazy ladies. Long story short my mom and MIL have gone completely off the deep end about this baby (first grandchild on both sides) and they want to start buying at least some stuff. They can't help themselves! They are women possessed!
Anyway, my question is what baby stuff have you found invaluable in the past or what have you seen others use that you will invest in? Stuff that you didn't think you were going to need or didn't think about would come in handy too, because if they are going to do this I want them to get stuff that is off the beaten path (not blankets or clothes) I am the first in my group of friends to procreate and I have no idea what I am doing.
Thanks in advance for your expertise and inevitable silly remarks 
Re: Essential baby supplies
As this is my first child, I don't have any advice because I haven't done research myself.
Try reposting on 3rd tri, or even the 0-6 months board. The moms over there might have more input than first tri ladies. Good luck!
Pack n play are the best....
A good double electric breast pump if you decide to breastfeed and are going to be working or going to school, etc.
I lived in my glider for a few months, very important nursery item.
If you live somewhere with lots of extreme season changes, clothes in over abundance is a bad thing. DS had so many clothes that he didn't ever end up wearing because they were in the wrong season at the wrong size.
I loved having a boppy pillow and had several covers so when it got spit up on I could throw the cover in the wash and have another to replace it with.
I will try to think of more, but really at first you hardly need anything.
Really, there's not a ton that you NEED for a baby. We got so much crap. While I greatly appreciated everyone's generosity, you don't really need 45 blankets or teddy bears.
Really, all you need is a carseat, a place for the baby to sleep (crib, pack & play, bassinet, whatever), diapers, clothing and bottles (even if you plan to BF you'll want a few bottles for expressed milk)
Now, I do have a few items I could never have survived without: The boppy and the SwaddleMe.
DD #1 passed away in January 2011 at 14 days old due to congenital heart disease
DD#2 lost in January 2012 at 23 weeks due to anhydramnios caused by a placental abruption
Get on the Babies R Us website. They have some really helpful sections where they list best sellers and "mom's favorites", etc. They even have a rating system so you can see what people thought of a product.
I thought we didn't need a swing or an exercauser. Our first trip to Target after DD was born, I bought a swing. We bought the exercauser when she could start using it (about 4-5 months).
Unlike an above poster, I couldn't live without the diaper genie/diaper dekor.
Swaddling blankets are also a must. We ended up using the Arms Reach Co-sleeper to have DD sleep next to us in our room for the first few months-we'll definitely be using that with #2.
Let them buy you the infant carseat AND the convertible car seat-I was amazed how soon DD outgrew the infant seat.
Generally, I would say go overboard and then keep the receipts and return what you don't use.
I loved my boppy with my girls for both nursing and propping them up for a bottle.
One liked the swing and one like the bouncy seat...so these are hit or miss. The exersauser was a hit for both of them (but you only get a little bit of use out of it). The activity mat (we had a red, black and white one) was great when they weren't mobile.
Lots of bibs, and burp cloths got used at our house. Happy Shopping!
I won't remember everything, but here's a few (although not all are a need, these are some faves):
carseat with 2 bases if you have 2 cars
SWING- most DC's live in these the first few months. ours was a grayco swing base that our carseat hooked right into. only $50 and DS could go straight from the car to the swing and stay asleep. LIFESAVER
we also used a swaddleme- but I know some babies hate being swaddled, DS loved it
wipes warmer- everyone has their opinion on this but DS was much calmer with a warm wipe than a cold one, especially in the middle of the night
pack'n play that is light enough to easily carry
a stroller you love- we loved having one our carseat would hook into, and no you don't need a travel system for this to work
boppy with 2 or more covers
2 or more crib sheets
we have a toy holder for the bath tub that looks like a frog & hangs on the wall- it drains all the water. around 6 months this became a space saver for our tub, love it.
a friend of my mom's who is a nurse put together a medical basket which was awesome- baby tylenol, sun tan lotion, gas drops, baby nail clippers, a good EAR thermometer, etc. THIS WAS A LIFE SAVER!
moitor- ours was only $30 and it worked great (plus it had 2 receivers, 1 for our room and 1 for family room)
baby carrier but this is def. a personal choice, there's A LOT of options out there
eventually a high chair- we have the fisher price space saver version that fits right into our kitchen chairs, love it.
one of my "don't waste your time" items is a bottle warmer- it was easier & faster to just use an xlg cup filled with hot water for a minute
hth! (go onto the 0-6 and 6-12 boards to ask what they loved and what they thought was a waste- it'll be fresh in their minds!)
I have one more to add to the list from the pp...
A microwavable bottle sterilizer. I have an Avent one and I loved it. Even if you don't use the Avent bottles, you can still use other bottles. If you use a taller 8oz bottle, just put it on its side to fit in the sterilizer. Another good one is the Medela bags. You can use 1 bag 10x and there was a bunch in the box (can't remember how much).