Ben beat me to it, but Flaming Familiar is the most underrated spell in the game, let alone for a fellow conjuror. I first came to love it when I scrambled over the mountains from Bilegulch Mine to attack the Forsworn camp at Lost Valley Redoubt - until then I hadn't realised its huge range, easily twice that of an typical Destruction spell. I simply sat high in the rocks above the camp, well above their arrow range, and conjured one firedoggie after another until I'd taken down the entire camp without them ever laying a finger on me. And just last night I cleared the final boss fight in Folgunthur while standing about 200 yards outside the chamber where the battle was going on! Some might argue that there is a certain sneakiness to Conjuration, but for me it is exactly how I imagine a mage's power to be; an effortless, almost contemptuous rise above the gruntwork of combat, deploying my supernatural powers to do the heavy labour for me. I cannot wait to get my Dremora Lords back in action.
Also, a simple tip - when attacked in tight corridors, conjure a Frost Atronach directly in front of you. Nothing can get past Frosty, and you are completely safe to hang back and throw in the odd rune until he's crushed the enemy.
I like this comment Kged, my feelings exactly...
While we're on the subject, the Dremora housed in the Sanguine Rose also has an insane cast distance. Dropping a dremora right inside a bandit camp is awesome...
He also scales with your character so as you level up his power grows until he actually outclasses a summoned Dremora Lord in terms of hit points. Dremora Lords still win in terms of overall damage though because their weapon is enchanted with fire...
Still, if your character doesn't use conjuration the Sanguine Rose is a really good toy to use! Dremora are slightly more pro-active than other summons and love to chase things down for you shouting all kinds of demonic insults as they slay...
The only thing I dislike about my xbox is how sensitive it is.... On the xbox the power button and open tray button are sensors, it seems if I walk too close it turns off .
With conjuration I have never noticed that, but it kind of makes sense. Its like a command undead spell. I will test it when I have time (I have a strong necro character sitting around).
I remember I loved my Conjur-build, until I got to the last stage of the Mage-Collage arch....
/spoiler (aka, don't read on if you haven't done the mage-collage-arch yet)
All my summons got turned on me, or banished... since I was a complete Conjur-build, I had no way of dealing with the priest.
/spoiler over
But other than that, the build was fun overall... sadly i won't do a conjure build until after the mage-collage-arch again.
I made and extremely effective conjurer build utilizing stealth. I'd sneak around and use silent cast to throw a couple of antronachs on my enemies and use a bound bow from hiding. If I needed to get down and dirty I'd use bound sword and dragon skin and then go to work.