I used to use any old, cheap earphones I find on the go and over the head headphones at my computer but last year I discovered the joys of in-ear phones and I haven't looked back. They block a lot of outside noise and voices come through really crisp, nice and clear.
The pair I own are made by a brand called Go, which is not really an audio company but a company which makes travelling products. I was at an airport and needed a pair of earphones and these were the only ones available in the bookshop. They have turned out really great. They are retractable which makes them durable.
Previously, I used to stuff my earphones into my pocket and they would break after a few months. Retracting them in a second before putting them in your pocket keeps them in good shape. I also used to wait long minutes untying knots in the wire when using them again. Retractable earphones solves this as well.
The only downside is that the coil into which they retract can feel heavy or swing around if you're moving vigorously and if it's not held firmly under a belt or something, or if you are not sitting down.
These are the earphones which I'm talking about.
http://go-travelproducts.com/us/elec...tractor-phones