Amelie, Chocolat, Groundhog Day, The Princess Bride, Roxanne... I know I've seen some of the others mentioned on this thread, but I can't remember them well enough...

His Girl Friday
Waking Ned Devine
The 5th Element
Miss Pettigrew Lives for a Day

Patterson is a good one.

The Note Book and What Dreams May Come.

Something's Gotta Give

Crazy, Stup-id Love (Agnostic.com deletes the words "stu-pid and s-x.)

The Birdcage" with Robin Williams and Nathan Lane. Hilarious!

Waking Ned Devine

Leap Year

Moonstruck

When Harry Met Sally

Made of Honor

Must Love Dogs

I like love stories and murder mystearies. My favorite love story is "Somewhere In Time" with Chistopher Reeve and Jane Seymore. A little old but so am I.

A Dog's Purpose
The Thing You Do
Spaceballs

kingpin

something about mary

The quiet man
The african queen
Zulu
The Italian job (original) Benny Hill and Noel Coward
Oh brother where art tho
Truly, Madly, Deeply
A matter of life and death
The lady Killers (Coen bros remake) Rocky Casablanca One flew over the cuckoos nest Dr Stangelove The taming of the shew (Taylor and Burton) Classical rom-com Whatever happened to baby Jane Citizen Kane On the waterfront (to be frank any Kubrick film) Ice cold in Alex Its a wonderful life
The red violin
Cinderella man

Oh I could go on...and on

My favorite romantic comedies are Kill Bill (both of them) and the Blues Brothers.

When I read the post, I was not sure if the question was favorite movies or favorite romantic comedies. Judging by the responses, I assume now the latter.
When Harry Met Sally; Love, Actually; Relax, It's Just Sex; Mambo Italiano; Summer Storm; Regular Guys; Forget Paris; Home For the Holidays; Bringing Up Baby; Roman Holiday; Torch Song Trilogy. ...So, okay, some of these are romantic dramedies, or coming of age stories with romantic comedy elements. I do love me some Hepburn, both Katherine and Audrey!

RomCom, Along came Polly.
Comedy, The hangover.
Thriller, The others.
Sci-fi is my favourite genre so couldn't pick just one.

Saw a 'walk in the Clouds' recently, great film with some 'magic' moments. Also have a look at 'Bladerunner' if you haven't seen!

I liked audrey hepburn in the grass is greener -

If You've Got Mail is a favorite, have you seen The Shop Around the Corner, the Jimmy Stewart classic on which it's based?

Gattaca, Sunshine, 28 Days Later.

As far as rom-coms go, blast from the past and notting hill.

I like romantic science fiction...
Time Travelers Wife
The Adjustment Bureau
Passengers
Oblivion

dredd

the thing

Romantic comedies...

'What's Up Doc?'

'Bringing Up Baby'.

The way Katherine Hepburn has an attitude tickles me. I love the humour in some romantic comedies but some modern ones don't work as well.

Stormy and Donald ! Oh sorry, thats not a movie yet ??

Casablanca is my all time favorite.

Romancing the Stone, Jewel of the Nile. Kathleen Turner, simply beautiful.