My S/O decorated the apartment as a surprise to me. I went out to pick up my friend for the celebration and when I came back it was decked out in Little Mermaid theme (which has a special meaning for us). On top of that he also got me a jumbo 1/2 pound reese's peanut butter cup (my favorite candy). Then he got me a perfume set too.
Simple stuff but 2/3 of it meant something special and have good thought behind it.
We just started seeing each other (like, only a week) for his last birthday so I gave him a gift card and a special sexy outfit.