intro themes i like....
Chobits, Cowboy Bebop, Last Exile, Love Hina, Tsukuyomi Moon Phase(love the bossanova!)

of course! how could i have missed Chobits and Love Hina!?
Chobits intro have a brilliant theme song, even with a simple intro sequence the whole thing is very effective in introducing the series! and the Love Hina intro is great! with character introductions and fun music!

Wow, people who actually pay attention to the beginnings and endings. I always used that time between episodes to use the bathroom/grab food/stretch...

However, by far, my favorite intro was the Ruroni Kenshin Freckles opening, since that was on cartoon network, and I already had the commercials to take care of 'business.'

I didn't read the full forum ^-^ so sorry if it is a repeat, but my favourite is inyasha, Affections Touching Accross Time, is a vry enchanting song to hear ^-^

My favourite opening are:
Air
Tenjou Tenge
Escaflowne
Full Metal Panic - Fumoffu
Slam Dunk
Mai Hime
Hanayuko Maid
Shingetsutan tsukihime
Neon Genesis Evangelion

My Favourite ending:
Hanayuko maid: la verite
Bleach 3ed
GTO (shizusu)

The Op & Ed:
AMG OST & TV
Gunslinger girl
Love Hina
Grenadier
Midori no Hibi
Full Metal Panic

Opening's:
Generator Gawl (I want out)
OVA AMG
OVA Tenchi Muyo (first series only, 'I'm a pioneer' bugs me)
Full metal panic, awesome guitar opening and great lyrics
Blue gender

Endings:
Congradulations (AMG OVA)
Talent for love (OVA TM)
FMP (very sad)

I want to add Mahou Sensei Negima and Full Metal Panic The Second Raid

intro= air. i downloaded the serties and watched the intro every time. love the music nice and loud^^
ending=....... i say amg. cas usually i skip the ending to hurry onto the next ep so i dont see many endings:P

Yes, Air's beginning is very beautiful like the music inside the TV Series.
Today i watched the firts Chrono Crusade's episodes, the beginning is very cool! I like it!

I finally got to see Love Hina in full, I'm adding it's opening to my list, it's rare to find an opening that is at once annoying and endearing ^-^

You are very right about Love Hina's opening.

my 2 favorite is Bleach and Naruto openings (and endings as a matter of fact)

The third ending of Bleach is cool too, they show the various captain' s squad and them liutenant

Begining- Mars, chobits,
ending- Oh My godess,

I'm adding the opening to TM season three now that I have seen it, anyone who has seen it and read my bio will understand lol ^-^