There are many of mixed blood purities in the house. Snape and Tom Riddle were both Half bloods as was Pansy's best friend. There were also a few Muggle borns as mentioned in the DH book.
Slytherin has long since changed from being a pureblood haven and only dishing out bad wizards.
Notable good wizards from Slytherin are Andromeda Tonks and Horace Slughorn.
Slytherins also love hufflepuffs as they are fluffy.
Slytherins are as smart as Ravenclaws but darker, as powerful as Gryffindors but think before they leap and are loyal to their family and friends like a Hufflepuff.
Never tell a Slytherin they aren't a true Slytherin.
Every Slytherin will be led to greatness.
Merlin was a Slytherin one of the greatest muggle rights activist.
The Slytherin dorm is under a lake! That is like a free aquarium without having to pay a stupid fee. Put your finger on the window and see if a fish follows it.
One of the four 'houses' at Hogwarts.
Usually consists of the most ambitious and power-hungry students
Their mascot is the serpent.
~Taken from The Sorting Hat's New Song (OotP)
...And he'd kick the shit out of all those Gryffindor pussies too.
"I'm in Slytherin."
"I heard Samuel Jackson was in that house."
"It's Samuel *L.* Jackson, but you can call him 'Mr.Jackson', bitch"
Slytherin is the best house out of the four because the students who are sorted in this house are:
A.) extremely Sexy
c.) Not afriad to speak their mind
f.) Great Leaders
i.) We have cookies
The students in Slytherin ARE NOT always] mean, degrading, bitchy, and slutty. Although, we can be.
Students in Slytherin
-Tom Marvolo Riddle Voldemort
Slytherin boys have big wands.
Slytherin is the best house.
He is stupid he must not be in Slytherin.
Harry Potter is too much of a pussy to be in Slytherin.