The gate out of chorrol has two items, a bow and a mace that are worth getting. You can find this gate at random in other gate locations, but it's always the Chorrol gate. check out the wiki for directions on how to find. What are they called? Darn my poor memory, something like Hatreds Heart. The bow has the most base damage in the game if you use the arrows included. I use the copy glitch and make more arrows. I believe you have to be level 25 to get the best versions, but check on wiki. They list every gate type and by looking up Chorrols you'll see the items I'm describing.
the normal way I check at random gates is to first look for a leaning tower. That in itself is not enough because there's a gate area that also has a leaning tower and is another kind entirely. This tower has to be surrounded by lava. There are islands and a downed gate lying in the lava. You get over there using a walk on water spell or echantment, or by taking a flying leap. You can also island hop to the correct island. On th far side of the small island is a door out of sight from on top. You must go to the lava's edge and you will spot it. Kill the two key holders and use the keys to get to the bow and the mace. There's another prize located in a hole surrounded by lava in this area but I've never been able to access it.
Yup, what Old Grog said...
Best Item: Hatred's Soul (Bow) and Hatred's Heart (Mace). I used to save before entering OB gates, just so I can find the right one. These weapons are hidden in a special OB gate. The cave is called "The Fume Vaults" it was one of the best kept secrets when Oblivion first came out!
http://www.uesp.net/wiki/Oblivion:Random_Oblivion_World_2