#1 Kat Von D, Tattoo and Ink Liners
This is my favorite liquid felt tip eyeliner of all time, the stuff doesn't smudge or budge, and it's pretty well pigmented as well. I recently noticed KVD has came out with some new colored eyeliners (in the Ink collection) which in my opinion makes it more of a contender with the Stila eyeliners in terms of color selection. KVD eyeliner is the best of the best for your buck as it's typically cheaper and contains more product than that of my second favorite eyeliner brand mentioned on here.. Stila.
#2 Stila, Stay All Day Eyeliner
Most of these liners work just as well as the KVD although I found some of the colors to not be as consistently pigmented and such (although I kind of like the color options Stila has a bit more than what KVD currently offers), which can be disappointing if you don't try them out before purchasing. These also tend to be a bit more money and a bit less product compared to KVD which makes these my second favorite felt tip liquid eyeliners.
#3 Rimmel, Glam Eyes Liner
For a long time this was the only drugstore eyeliner that really worked for me in terms of application, and while the tiny tipped applicator can seem a bit daunting it just worked better for me at the time over pens, gels, etc. that I had been trying at the time. It's not the greatest in terms of being smudge proof as the previous two eyeliners mentioned on here but it's worth a try if you're on a budget and wanting something a bit more concentrated to work over your eye makeup.
#4 NYC, High Definition Liner
If you're looking for a natural looking eyeliner to avoid the boldness of these other eyeliners mentioned, or you're someone just getting into wearing and using eyeliner then this inexpensive gem could be for you. Megan Fox loves the stuff and I have to agree, it's pretty great for natural eyeliner looks and it's fairly easy to apply with its felt tip applicator.