We started playing an eberron campaign a couple of weeks ago and I was really taken with the artificer class. I view it as the ultimate flexible support class with some real fun opportunities for role playing, depending on how you do it.
The ability to infuse enhancements into weapons and armor, modify energy protections, and make a wide variety of scrolls and potions is extremely fun, and I've enjoyed doing the research to figure out what Sidorius Lore would be focusing on.
Sid is now 4th level and has taken Magical Aptitude and Skill focus (UMD). With an 18 intelligence the UMD checks are very solid now so he's only failed to make a scroll one time.
What Sidorius has focused on in the first few levels is to build a collection of scrolls that are useful in those niche situations so the other party members haven't got to prepare them since they don't come up that often. He's also focused on the search/disable ability to back up the rogue, and finally spent points on knowledge classes to fill in where the wizard is lacking. One special ability that has been really fun to grant to weapons is the 'bane' ability. It's +2 bonus and extra 2d6 damage were really appreciated by the fighter in the party and Sid enjoyed watching the carnage as well when we came up against a collection of spiders early on...
But my favorite was when we fought a young white dragon in a mountain pass, changing the fighter and the rogue's weapon's to flaming weapons was really enjoyable, all they while enhancing my own warforged armor to be cold resistant. It was a great encounter and everyone enjoyed the enhancements as much as Sid enjoyed passing them out.
I think the one thing that I've spent the most time tinkering with, and haven't come up with a solid list of yet is, what scrolls he should always keep around, and now that he can make 3rd level druid/cleric/wizard based spell scrolls, which ones should he be doing next...