Depends. When are you presenting the gift? Alone, or at a party? My kids seriously had more play time with strings/wrapping paper than they’ve had with some of their toys.
If you want to get a gift that’s hard on a parent ;). Any toys that are noisy, but do not have shutoffs. Most of the bigger toys with have on/off and volume switches, but some smaller toys simply play their tune and shut off. My parents bought us a tiny play boombox that has three different short tunes it plays. The noise level on that thing is extremely loud, and there’s no shutoff - you have to let it finish and hope the button doesn’t get pressed again.
For a more serious gift, all three of my kids loved playing with Fisher Price’s Little People. My three-year-old still plays with them.
Clothes, even a size up from what they’re wearing now, are good. Savings Bonds are also really practical.
Books are good if they do not already have a ton of them. I have enough county and letter books to supply an entire preschool. IMO, books with sound boards and stuff are overrated. The kids just ended up playing with the sound buttons, or just looking at the pages. It was only when we sat down with them and hit the buttons on queue that they were used together. Nice, big, flashcards are good too. Not the small, deck-of-cards sized ones.
Bubbles are great…especially machines that can spit them out for you…just set it and forget it, the kids will come tell you when they’re gone.
I would really recommend any kind of learning DVD. I know some people are against putting kids in front of a TV, but my Aunt introduced us to Signing Time and my two and 3 year-olds love to watch it and picked up all kinds of sign language that they use right now.
More movies are Preschool Prep - The movies are very annoying to watch with them, but the kids are mesmerized. My youngest daughter learned all her numbers, letters, and some sight words before she was two.
Leap Frog has some stuff as well. My kids are currently going through the Letter Factory DVD. Even though they know them already, they still love to watch and sign the songs.
My Experience? Three kids between the ages of one and five. My wife insists on big birthday parties for every birthday, and also we have three family Christmas parties to go to each year.
EDIT: Sorry about the formatting, I did it quickly while at work.