I got quite lucky some time back and got the book for $3 in good condition.
Although most of the technical details are obsolete nowadays, I would still recommend it.
Abrash's writing style and the way he approaches problems makes it one of my favorite technical books out there.
And if you think about doing Mode X stuff - buy it, read it, love it!
Although it doesn't have to do with the book directly (but highly recommended),
Fabien Sanglard does a great job analysing the IdTechs and others
http://fabiensanglard.net/
