DF Felltower features some intelligent items. Not a lot.
There are several items people have ascribed intelligence to, but which totally lack it - they're merely magical effects. One example is the Targe of the Tiger (a variant Ward of the Wolf). It does something on its own, kind of, but it's just an effect of magic that makes it appear to be a living thing in some ways.
A couple of items and spells summon intelligent-ish beings - temporary magical effects in the form of an animal or humanoid form. The Statuette of the Death Goddess and Dragon's Teeth do that, as do Create Servant and Create Warrior and Zombie. They have some intelligence, but they're not sapient or independently thinking. They're more akin to a pre-programmed thing that can handle limited if-then situations.
There are all of three known intelligent weapons in Felltower. Agar's Wand, Malice, and Sigurd's Sword (aka Gram, Balmung). That's it.
Sigurd's Sword is intelligent, and communicates in feelings to its owner. It has its own goal - dragonslaying* - and imparts some of that onto the bearer directly, and the rest by projecting feelings the bearer can sense. Sigurd's Sword can't do much of anything on its own, it needs a bearer it can push and steer.
Malice is semi-intelligent. Possibly more, but there isn't anything to support that. Malice can only be malicious, and remember slights and force the bearer to strike first, strike hard, and show no mercy. It also can't do much directly to affect the world around it without a bearer.
Agar's Wand is intelligent. It is self-willed and able to act on its own. It sometimes will. Its goals are broadly clear (fight evil) but vague in implementation and in what "counts" towards that goal. You can count on it to defend a good bearer, and fight effectively when it has something to fight for, but you can't direct it around. It won't direct its bearer, either - you're either allies or it's not working with you. It's also, incidently, the only Weirdness Magnet in the campaign, given that I do not allow it as a disadvantage on PCs.
That is a complete list of known intelligent items. There may be more, but I wouldn't bet a PC's life on it.
Intelligent items are an interesting plot device and Deus Ex Machina in books. They're a bit more of a problem in games, in my experience. I don't use them heavily because I don't want to either hand out an Ally or have another NPC to run. I have one - Agar's Wand - and that's plenty. My players tend to ascribe intelligence and will to things that lack them, which is interesting, but doesn't add an IQ stat to anything.
The intelligence on those items serves a purpose. If they weren't intelligent, they wouldn't work as effectively. Sigurd's Sword without intelligence just has a negative effect ("Go fight that dragon, NOW!") that people would want to resist because, well, rationally, fighting the dragon later is a better choice. With intelligence you're angering your magic item and might not get to keep using it. Agar's Wand without intelligence has nothing except a PC to direct it, just making it a weapon that fights for you, and, thanks to conflicting enchanments, doesn't do it very well at all. Malice without intelligence is just a cursed sword with some upsides, and sparks questions about Remove Enchantment and Remove Curse as way to keep the upsides and remove the downsides. Intelligence binds their properties together into one thing - you can't see removing one without the other, or ignoring part and keeping the rest.
But the meta-game cost of it is high - lots of work for the GM, another NPC to run or to hand off to the players to min-max value out of. And therefore intelligent items are going to remain rare in DF Felltower.
* And presumably, saving Bwunhilda, she's so wovwy.
