My daughter Sophia is 13 months. Here are a couple of her favorites (some of them she's had for a while but still enjoys):
* Rubber blocks by "Parents" (brand made for Target) it came with a couple cloth books - the blocks are great!! When she'd stack more than two blocks, I would clap - now she claps for herself and gets up to 7 stacked high (it's so cute to see her clap for herself :-)
Rubber inflated balls - about 5 inches - bought at Toys R Us - she loves it when we roll the ball to each other and then sometimes just likes to through the ball and chase after it herself.
Flip Books - her favorites are the Karen Katz lift the flap books - Where is Baby's Bellybutton is a great book for them to learn body parts. (she can now point to my nose, eyes, ears, etc.) You can usually find them for less $$ at stores like TJ Maxx
Also - she loves the Brown, Brown Bear (What do you see) book and other books by that author.
A play Tunnel (it collapses) I got the one at Toys R Us that's about 7 feet long and can attach to a little tent. - she loves to play in that.
Electronic toys:
Leap Frog Learning Table- has had that for many, many months - still loves it.
V-Tech Telephone
I'm looking also for some other toddler-centric toys too.