Hmmmm, it was a while ago so let me think. Disclaimer: My boy had severe colic until he was 4 months old and he spit until almost 10 months. So most of this will be hindsight ;)
Best:
1. Bouncy chair. It was the only,ONLY thing that would calm Mr. down. He is now a year old and I still use is sometimes. In fact there is a post on here somewhere from when I was trying to wean him from it at 9 months old!
2. Cloth diapers as burp rags. My MIL kept telling me how much I would use them. (Yah, right I thought). I HAD to have these. The decorative burp clothes did NOTHING for the amount of spit that came from my boy.
3. Angel Baby Monitor. It IS NOT a hospital grade apnea monitor but it did make me feel more secure. Mr. WOULD NOT sleep on his back so we put him on his side and I felt ok.
4. Hangers, I know that sounds silly - but at least I didn't have to buy a BUNCH for all the clothes he received.
5. After we stopped swaddling we used the sleep sac as his blanky. Now that it's getting cooler I need to go on the mad-hunt for one his size. If they make it ;)
Worst: I know it's not 5, but I'm out of time for now!