[ericbsmith]

Yes, and no, and kind of so. First the question has to be asked how you want Magical Items to be represented? Are you talking about using the standard Enchantment system found in GURPS Magic? Or something else?

In the standard Enchantment system there are several ways to boost a weapon's damage. Flaming Weapon (Magic, p. 75), Icy Weapon (p. 185), Puissance (p. 65), and probably a few others enchantments can be added to a weapon to increase their damage. For the classic "this weapon is better at hitting" you can add the Accuracy Enchantment (p. 65). For any of these, if the bonus only apply to a limited class of creature (e.g. Dragons) you can add the Bane Enchantment (p. 62) which make the other Enchantments easier to cast and reduces their cost.

For attributes, the magic system tries not to allow Enchanted items which give permanent advantages or attribute boosts. These are best represented as Gatgets (p. B117-118). Despite the name, a Gadget is any piece of kit which grants an advantage. Take Extra DX (20/level) with some form of Gadget and Mana Sensitive (p. B34).