1) The "sewn-to-the-top" handle
classic Blackhawk 3-day pack
Seen on panel loaders, this is just sewn onto the top are of the pack. Works fine for smaller packs.
2) the "sewn-into-a-seam" handle
Seen on most everything not a panel loader (and some of those too). Must be suitably reinforced on larger packs.
Some variants on the theme:
ILBE assault pack, sewn-to-the-top but anchored into some seams
MOLLE II ruck, handle is actually anchored in the direction that force is applied to the seam. Also anchored into two separate pieces of webbing that spread the force over a wide area.
My favorite so far, and the inspiration for this inane post:
Look closely, the entire handle is set into the dished out "head-room" area (is there a real name for that spot?) and is anchored to the pack at an angle (like the direction that force is applied to the pack through the handle). The handle is also a nice tubular webbing stuffed with something squishy (plain old webbing kind of sucks for picking up a 60lb pack).
I first noticed this handle on my wife's REI Venus 75 pack, and then later on my own REI XT-85. While the grab handle isn't all that important this is the sort of small detail that not only makes using the product slightly more pleasant but shows an intentionality of design that I appreciate. If the rest of the backpack sucked I probably never would have noticed this feature, but added together with many other features REI has risen considerably in my mind from being the "house brand" to a serious contender in the pack market.