My favorite magic item is the wand of wonder. There’s a number of items of random magic in the game (bag of tricks, deck of many things, etc.) but none of them strike me as whimsical as the wand of wonder. The wand has a nice balance between effects: they are funny (turning permanently purple), useless (grass grows), damaging (a 6d6 fireball), and useful (invisibility).
I use the wand often. Recently, I gave the apprentice mage Lessie in Three Sad Wizards a variant wand of wonder. For her wand I removed the more damaging effects to make it less deadly and more humorous. Quinzel from Faces of Pretomournon has a wand of wonder as well.
Why WotC thought they needed to change the wand into a rod of wonder is beyond me. Just another case of fixing things that aren’t broke. Wand or rod, this magic item is always fun.