Intelligent Artifice (Feat)
Prerequisites: Int 15+, Use Magic Device 4 ranks.
Benefit: You may use Int instead of Charisma for Use Magic Device checks and you gain a +2 bonus to Use Magic Device checks.

--

I'm a little iffy about the +2, as it currently stacks with Magical Aptitude and Skill Focus (I might amend it not to stack with Magical Aptitude) but I just always want a smart artificer (even when making NPCs) or rogue who can use his wits, cunning, and smattering of learning in magical lore to fake an item instead of charisma. Maybe I should add a Knowledge (arcana) requirement as well.