Tongue Twisters :O

• The sixth sick shiek's sixth sheep's sick. (A variant on what the Guinness' Book of World records considers to be the hardest tongue-twister in English).
• She sifted thistles through her thistle-sifter.
• Give me the gift of a grip top sock: a drip-drape, ship-shape tip-top sock.
• Moses supposes his toeses are roses, but Moses supposes erroneously. For Moses, he knowses his toeses aren't roses, as Moses supposes his toeses to be. (from "Singing in the rain". Danny Kaye also a great supplier of tongue-twisters).
• While we were walking, we were watching window washers wash Washington's windows with warm washing water."
• "Peggy Babcock" (to be said rapidly three times).
• Red leather, yellow leather
• Rubber baby buggy bumpers (a baby buggy in American English is a pram in British English in case this one makes no sense)
• A lady sees a pot-mender at work at his barrow in the street.
  "Are you copper-bottoming them, my man?"
  "No, I'm aluminiuming 'em, Mum"
• Freshly fried fresh flesh
• Six twin screwed steel steam cruisers.
• The crow flew over the river with a lump of raw liver.
• Preshrunk silk shirts.
• A bloke's bike back brake block broke.
• Good blood, bad blood
• Mixed biscuits.
• She stood by Burgess's fish sauce shop welcoming him in.
• Tie twine to three tree twigs.
• I am not a pheasant plucker
  I'm a pheasant plucker's son
  but I'll be plucking pheasants
  When the pheasant plucker's gone. (careful with this one)
• She sells sea shells on the sea shore, the shells she sells are sea shells I'm sure.
• Czech:
  strc prst skrz krk [all 'r' are vocalic]
  'stick [your] finger through [your] throat'
• German:
  In Ulm und um Ulm und um Ulm herum.
  "In Ulm and around Ulm and around Ulm again."

From Eric Nünlist, a sample in:

• Swiss German:
  Der Papscht het z Spiez ds Schpaeckbschteck z'schpaet bschtellt.
  "The pope was too late to order the bacon cutlery in Spiez"
• and another:
  Wie würde Wettiger Wyber Wösch wäsche wenn Wasser Wy wär?
  "How would the old ladies of Wettingen do the laundry if water were wine?"
• and another (my favorite):
  Schtell der Hafen afen ufen Ofen ufe
  "Put the pot on the stove for the moment"
• One in Dutch:
  Sevenenseventig scheweningse beschuitjes
  "77 rusks of Scheweningen"

And a few others from random sources:

• From Noel Piercy:
  Toyboat, toyboat, toyboat
• From Laurie Brasile:
  Unique New York
• From Jan Gorden:
  The seething sea ceaseth, and thus the seething sea sufficeth us.
• From Johmanda One-Name:
  One smart-feller - he felt smart
  Two smart fellers - they felt smart
  Three smart fellers - they all felt smart

And finally a lengthy one from the band Trout Fishing In America:

We weary deer live in fear, weary deer,

For we fear that hear the hunters near,

with a tag for the toe of dear John and Jane Doe,

Oh no! We are wary weary deer.

Hunt the moose, or the goose, but please turn the poor deer loose,

for our families would miss us if we're not here

We stay up all the night in a terrible fright,

Pity us, bleary wary weary deer.

Oh, the foot of the hare brings good luck beyond compare,

and the hair of the bear is more impressive.

That space on your wall could use a nice trophy trout--

Think about it, think about it.

While we weary deer live in fear, weary deer,

Hiding down in the deep damp dark dank den (in the gloom).

How we long for a day with the antelope to play!

Oh, surely some sunshine shall shine soon.

Hunt big game if you must, they're more glamorous than us,

Or a feast of feathered fowl is delicious.

The stand so pround and so tall that they must

present a target that'll make you want to skip us.

Steer clear of the deer, we live in fear, weary deer,

For we fear that we hear the hunters near.

With a tag for the toe of John Deere and Jane Doe,

We are leery bleary wary weary deer.