I got a lot of questions about flats after writing this post, so I thought I would introduce you to the four pairs of slip-on ballet flat type shoes currently in my closet - tell me about yours in the comments:
1. Gap leather flats with quilted footbed: These were my first pair of Gap flats. I bought them one day in NYC when I was hobbling around in some horribly uncomfortable yet fashionbale shoes that caused me so much pain, I could hardly walk. I ducked into Gap and bought these flats for $40, slipped them on and experienced the most sublime relief. They have remained one of my favorite flats because they're super comfortable and have a very low profile and understated elegance that I love.
2. Pour la Victoire studded flats: I have a love/hate relationship with these shoes, which I purchased for something like $80 on Gilt.com, which is a lot for me to spend on a pair of shoes. I'm convinced these shoes are trying to kill me. The first time I tried them on, I slipped on the smooth leather soles while walking down stairs and nearly plummeted to my death. My back hurt for two weeks after that fall. I proceeded to scuff up the soles for traction prior to wearing them for a second time, but after wearing them for a few short hours, they began to cut into my feet so badly that my feet nearly bled. Still, I like the look so I'm hoping that by wearing them for shorter intervals, I will eventually break them in!
3. Ras silver flats: These are my subtle silver leather flats by a brand I had never heard of before, which I purchased during a final clearance sale on ideeli.com for something like $50. These were really painful at first and cut into my heel. I was ready to throw in the towel when a reader recommended Band-Aid Blister Block, a product that rolls on much like deodorant - you apply it to your feet and it magically blocks friction and prevents blisters. It's not really a miracle cure, but it allowed me to wear these flats for a few hours at a time, thus breaking in the shoe to fit my foot. Now I can wear these pain-free, sans Blister Block. Love the look.
4. Gap leather ballet flats: My "Repetto knockoffs." I purchased these during a second trip into the city when once again, I found myself limping around in fashionable yet painful shoes! I ducked into a Gap and all their flats were on sale, meaning my size was sold out. Then I spotted this pair on a mannequin and asked a sale associate if I could buy them. She gladly helped me get the shoes off the mannequin and I walked out with happy feet. I'll admit these shoes feel like slippers but they are so chic and comfortable, they're among my favorite shoes. I wear them with cheap-o insoles from Walmart to keep them looking new, longer. I have nothing bad to say about them!
Ok, your turn!
I need help finding the perfect pair of really comfortable basic black or silver flats. (Comfort is key!) Hopefully, under $40. Please help! —Catherine 
My absolute favorite flats are from the 
