Various issues of the following magazines can be collected to gain the listed bonus.

Magazine	How to unlock
Astoundingly Awesome Tales	Typically add 5 percent to damage against a selection of enemies or make it easier to heal radiation damage.
Grognak The Barbarian	Typically add to the damage dealt with melee or unarmed attacks.
Guns And Bullets	Add about 5 percent to critical damage.
Hot Rodder	Cusomize Power Armor with up to three new paint jobs.
La Coiffe	Two new hairstyles.
Live and Love	Add perks to influence companions, or give you an extra boost when they are around.
Massachusetts Surgical Journal	Increases limb damage by 2 percent.
RobCo FUN!	Get Holotape games.
Taboo Tattoos	Get up to five different tattoos.
Tales Of A Junktown Jerky Vendor	Improve prices when purchasing from vendors.
Tesla Science	Add 5% to your energy weapon.
Total Hack	Hack through Protectrons, spotlights, and turrets.
Tumblers Today	Bonus on lockpicking.
U.S. Covert Operations Manual	Improved sneaking.
Unstoppables	Add 1 percent of avoiding all damage from an attack.
Wasteland Survival Guide	Collect extra meat from all animal kills.
You're S.P.E.C.I.A.L.!	Typically add 5 percent to damage against a selection of enemies or make it easier to heal radiation damage.