Phipps is a very special place for me as it's where I used to go to relax with friends after the end of each semester during undergrad. Although my friends have mostly moved away, I still head over when I need a break, especially during the winter months, and it almost feels like taking a small vacation. Tropical and balmy inside even when it's freezing outside - you should definitely leave your coat in the lockers provided downstairs (at the fair price of a quarter).
As for the place itself, it's beautiful! There are a lot of different rooms, each with a different theme. There's a desert room with all kinds of different cacti and unique glass art, a tropical room that makes you feel like you've been transported - weather and all. One of my favorite rooms is the one with an intricate setup of trains - the attention to detail to the miniature landscapes (different each season) is always astounding!
Local students get in for free during the semesters which is great, but otherwise the $18 for admission is worth it, especially for first time visitors!