Hmmm, I know:-
A AAA A AAAAAAA AA A
EVERY letter is an A 
Yet more words and geeky acronyms.
Proper nouns
Dan
Dana
Bananarama
Alan
Japan
Maya
Mayan
Tagala
Japan
Qatar
Baja
Sagan
Adam
Baba Yaga
Zabar (OK, so the store is called “Zabar’s.” Well, someone has to the be Zabar to whom that store belongs, right?)
Cara
Ada (This could also go under “geeky things.” I was taught to do some elementary programming in Ada, which might explain why I didn’t go into CIS. But I digress…)
Kara
Samana (It’s a place.)
Geeky things
NASA
GABA
Other stuff
Madam
saga
wan
kata
oak
oaf
fava (and a nice Chiaaaanti.)
(Now I’m waiting for sentences about Bananarama madams–or, rather, about one Bananarama madam–at a canal, at a bar, at a Bahama cabana–a saga a la Da Gama. Or about Sagan, a NASA wag.)
Lana, da Bahama Mama.
Ya, da Bahama mama, Lana Fala, was a yam… an’ Alan Adam, an Alabama banana man, ‘ad a lap… Aha! Sara May Adam saw! An’ Alan Adam a’ ran as a cad.
Allright:
A Fat Alana saw an Alabama banana man at a Canada caban far away.
USA! USA! USA! USA!
HAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHA…
Ferrous, my brother, did you forget the “!!!”? Or was that not a genuinely heartfelt vowel movement?
Feelings are at stake here.
Well, Lecy-boy, I felt the use of caps would adequately convey the EMPHASIS!!! I used the ellipsis points (…) to imply that the HAHA’s continued into infinity. This served the double purpose of expressing my great appreciation for your wordplay and adding my own contribution which had, in effect, an infinite amount of A’s.
Wow. If this wasn’t all mundane and pointless, I’d be forced to say that while feelings may have been at stake, now they are truly hurt. However, Ferrous really is my brother, (Older, as if there was any question about that)so no hard feelings.
Sorry to blow my cover Ferrous, hope you don’t mind if I tag along…
Oh, the shame of it all! To be associated with a rank newbie!
Yes, 'tis true: Lectricity is my brother IRL. I turned him on to the boards. Apologies to all*.
'S’okay, kid. You can tag along, but at least learn to code. Proper board ettiquette requires one to bold the screen names of fellow posters.
[sub]*Not really. Lectricity is a pretty good guy. Ask him a question about electricity or toys. Or clowns.[/sub]
Russians are always so pompous!
Alana saw an Alabama banana man, a hat, a bat, a cat, at a Canada cabana. Mama Rat!
Ukraina! 
Thanks for the words of wisdom brother mine, but we digress!!!
Sara, Dana, Bananarama fan, Alana, Baba Yaga, Madam Adam, Alabama banana man!!! They must-MUST-not be forgotten.
How about a sentance where every other letter is an “E” or an “O” or some other vowel, maybe even sometimes “Y”!
Is this not one of the more pointless of causes? Join in-
Call me “newbie”. Make me cry for more!
Sorry KneadToKnow, looked right passed you post, when I wrote this:
You posted a response straight away, that took me a couple of days to come up with, [sup]doh![/sup]
how bout this:
SHiehan went to the SHeeSHore to get SHeeSHells and SHrimp for her SHweet and Shour and SHalty SHpagetti Shoup
Come on, Win sorceress, reply!