Harry was feeling increasingly nervous about this whole thing. Sure, Ron had said there were lots of students who came to Hogwarts not knowing a thing about magic and did just as well and Harry had believed him. Right up until that girl Hermione came in and said she had memorized all the textbooks. And maybe Ron hadn't memorized all the textbooks, but he came from a huge family where, if Ron's stories were to be believed, they all did magic all the time. Not to mention that Harry didn't feel like he was particularly brave or hard-working or clever or cunning. In fact what he was feeling was a bit queasy and rather like that hat was going to make them kick him out of the school because he wasn't good enough.
Then Professor McGonagall called his name to be sorted and everyone broke out in excited whispers like his sorting was the most interesting thing since Merlin. And that really wasn't helping him feel better.
Well then, he decided as the Sorting Hat was slipped on his head and down over his eyes, he'd just have to prove he belonged here. He would find a way to be the best wizard he could possibly be, and prove them all wrong… er, right. Resolution made, Harry very nearly nodded decisively, before realizing that would probably throw the Hat off his head. Which, he was surprised to find, had apparently been talking at him for the last thirty seconds or so.
"You want to be great you say? I know just the House that can help you on your way to greatness." Before Harry could explain he wasn't really trying to be great, just good enough not to be kicked out, the Hat's brim open wide and shouted "SLYTHERIN!" And that, Harry supposed, was that.
The hall burst out into applause and even more excited, and possibly confused, whispers. Harry did his best to ignore them as he walked over to his new table, and very pointedly did not sit in the open spot next to Malfoy. Instead he sat between another first year who had just been sorted, Theodore Nott he thought, and an older girl who looked like she might take pity on him if he had to ask stupid questions. Theodore looked like he wasn't sure if he should be smug or angry at Harry sitting next to him, but the older girl smiled and welcomed him to Slytherin, so that was alright then.
Up at the front of the Hall, the Sorting had continued, but Harry ignored "Thomas, Dean" in favor of trying to catch Ron's eye. The red-headed seemed like he was a bit disappointed, but when he saw Harry looking he smiled readily enough. Glad that he still had one friend, Harry decided to ask if he was allowed to sit at other House's tables during normal meals, just in case all the other first years were as obnoxious as Malfoy.
Looking around the room, Harry realized that from his new spot he could now see the High Table clearly, including, at the end opposite him, Hagrid. Suddenly he heard "There's not a single witch or wizard who went bad who wasn't in Slytherin," echo in his head. But then Hagrid caught his eye and gave him a thumbs-up, so he probably didn't hate Harry because the Sorting Hat thought he was ambitious after all.
By this point all the students had been sorted, and Albus Dumbledore stood up to say some nonsense words. Harry was going to turn to the girl next to him and ask if their Headmaster might be a bit mad, when he caught sight of the piles and piles of food that had suddenly appeared and decided it could wait. Filling up his plate, Harry looked back over the day and realized he had made his second friend ever, tried a bunch of candy he had never even knew existed, managed to avoid getting kicked out of his new school, hadn't alienated anyone by getting sorted into the "evil" House, and was about to eat the most delicious spread of food he had ever seen in his life. Yup, it had been a pretty good day.
A/N: Because if Harry really got sorted into Slytherin it wouldn't cause a) the Great Hall to fall silent in shock b) Ron and Hagrid to hate him, or c) Draco to be his new best friend, despite what fan fiction may have you think.