In morrowind one had "packrats" -> rats that would follow you forever, and carry 100-150 weight (depending on what type they were)
there was no limit in the number of packrats one could have, but they DID had one downfall flimsyness (they were easely killed, as their defence was only as good as normal rats)

Later on you got to buy transport-kodo's. They could carry 500-750 weight (thats more than your own carrying limit)
they were tough, yet slow, but they'd do.

Does oblivion have anything that looks like it? like for example having mules or packhorses that follow you?

Also : in morrowind one could hire "assistance" NPC-fighters that you'd hired to fight with you (you needed to pay their wages regulairly or they would leave)
you could use their inventory as "225 free storage space" as well. and you could equip them with armour, potions, and weapons (they would use whatever you gave them, since when you hired them they often had very crappy gear)

They'd level up, just like you, so whatever weapon you gave them, they grew stronger in.
-> it was for some even possible to learn them a few spells, on the condition you already knew them and their skill was high enough to use them.

Does Oblivion has anything like this? having a gang of fighters is just more fun than being alone:)

Uhm .. Honestly, I don't remember pack rats or being able to hire help in Morrowind. Are you speaking of a mod that does this?

If so ... you can check out companion share and recruit on TESNexus. You can get some followers that way.

Personally, I prefer Vilja, by Emma & CDCooley. http://www.gamesas.com/index.php?/topic/1204219-relz-companion-vilja-ver-3-thread-no-10/ and I think Emma also made a pack donkey mod.

Packrats and hired assistance were added by the official extention pack Tribunal.

However in the basic game :
*one seller only had 6 rats, and he would not restock
*the rats could NOT leave Mournhold
*Hired assistance was part of some quests.. the only way to keep them was to not finish that quest
*hired assistance did also not follow you ourside of mournhold
*a pack-kodo excists in the basis-game, as part of a quest you need to asssist one, however the player never gets to own one.

All a mod did was make pack-kodo's available to players, made the packrat seller and assistance-hire place to restock, and allow packrats and assistance to leave mornhold.

ah, that explains it! I don't have Tribunal. At least I don't remember having it LOL!

No there's nothing like that in Oblivion. You have to mod it in. Unless you consider horses help. But most people consider them to be a PITA cause they die easily.