You'll find some curiosities in Gordon's locker. The two books, titled "The 37th Mandala" and "The Orchid Eater" are existing novels. The author, Marc Laidlaw, is also the writer of Half-Life.
The baby on the picture is Isabel, daughter of designer Harry E. Teasley.
In the locker room in the beginning of the game, the names on the lockers are the last names of the Half-Life design team. You'll find (Dario) Casali, (Greg) Coomer, (Ken) Birdwell, (Chuck) Jones, (Mona Lisa) Guthrie, (Douglas R.) Wood, (Steve) Bond, (T.K.) Backman, (Karen) Laur, (Dave) Riller, (Harry E.) Teasley, (Kelly) Bailey, (Brett and/or Erik) Johnson, (Jay) Stelly and (Marc) Laidlaw. The final locker, labeled Freeman, is of course the player's locker.
