Comic-Con International, held in San Diego, CA, is one of the largest conventions, one which receives thousands (and thousands) of attendees, some of whom are not even from America. It has become a convention for far more than Comics. In the past, it has even showed clips of the Harry Potter movies as well as clips from the set.
Though those clips are great treats, I must ask for more. Often movies will send cast members - both key or not - to Comic-Con for autograph signings and panels discussing the movie. I would understand if Daniel Radcliffe (Harry Potter), Emma Watson (Hermione Granger), or Rupert Grint (Ron Weasley) couldn't come; they may be busy filming the next movie (though if even one of them came it would be spectacular). However, I would believe that some of the more minor cast members (or cast from previous movies) could come and grace Comic-Con with their presence.
In alphabetical order by last name, some of those whom I am thinking of are (but not limited to):
Afshan Azad (Padma Patil), Sean Biggerstaff (Oliver Wood), Shefali Chowdhury (Parvati Patil), Alfie Enoch (Dean Thomas), Tom Felton (Draco Malfoy), Joshua Herdman (Gregory Goyle), Stanislav Ianevski (Viktor Krum), Lee Ingleby (Stan Shunpike), Katie Leung (Cho Chang), Harry Melling (Dudley Dursley), Devon Murray (Seamus Finnigan), Robert Pattinson (Cedric Diggory), James Phelps (Fred Weasley), Oliver Phelps (George Weasley), Clemence Poesy (Fleur Delacour), Chris Rankin (Percy Weasley), Jamie Waylett (Vincent Crabbe), or Bonnie Wright (Ginny Weasley).
It would be splendid if one or a few of them could attend, whether for an autograph signing or a panel (or both, if we're being ideal). If anyone agrees with me, they will sign below.

http://harrypotter.warnerbros.com/gobletoffire/index.html

Acne Life Insurance Death Insurance Bextra Asbestos Car Insurance Dental Plans 0 Private Jets Debt Consolidation credit Cards Rewards Cards Equity Loans Equity Line credit Loans Mortgages Pay Day Loans Cash Advance 0 Bankruptcy Reduce Debt Refinance Jet Charter Vioxx Wrongful death Legal Advice Taxes Investing Bonds 0 Online Trading IRA Rollover Refinance Quotes Adult Education Distance Learning Alcohol Treatment Rehab Drug Rehab Spyware Cell Phone Plans 0 Calling Cards VOIP Weight Loss Canadian Pharmacy Depression Spam Filter Lasik Facelift Teeth Whitening Annuity 0 Anti Virus Protection Adult Diaper Free credit Report credit Score Satellite Anti Spam Software Dedicated Hosting Domain Name Need Money Bachelor Degree 0 Master Degree Doctorate Degree Work at Home Quick Book Extra Money Eloan Malpractice Lawyer Lenox China Cancer Payperclick 0 Personal Injury Attorney Lexington Law Video Conferencing Transfer Money Windstar Cruise Casinos Online Term Life Online Banking Borrow Money Low Interest credit Cards 0 Personal Domain Name Cellular Phone Rental Internet Broker Trans Union Cheap Hosting University Degrees Online Online Marketing Consolidate Helpdesk Software Web Host 0 Homeowner's Insurance Yellow Page Advertising Travel Insurance Register Domain credit Counseling Email Hosting Business credit Consumer credit Blue Cross Laptop Computer