Hilton offers you to earn up to 10,000 Hilton HHonors™ Bonus Points by staying at participating Waldorf Astoria™ Hotels & Resorts or Conrad® Hotels & Resorts through December 31, 2014.
After registration,you will first receive 2,000 Hilton HHonors™ Bonus Points after completing one stay, than 3,000 Bonus Points after completing your second stay, and finally 5,000 Bonus Points after completing your third stay.
Waldorf Astoria/Conrad hotels aren't cheap but if you stay there anyways why not take the additional points.
According to terms and conditions this promotion is targeted, but you should try to register here. It worked for me.
Terms & Conditions
Offer is valid for recipient of this email only and is non-transferable. Offer valid for stays completed between January 23, 2014, and December 31, 2014 ("Promotional Period") at participating Waldorf Astoria Hotels & Resorts or Conrad Hotels & Resorts. Your stays need not be completed consecutively; stays completed are accumulated throughout the Promotional Period. However, an HHonors member that checks out and back into the same hotel on the same day will not receive credit for completing multiple stays. Hilton HHonors™ members may earn 2,000 Bonus Points for a completed first stay, 3,000 Bonus Points for a completed second stay, and 5,000 Bonus Points for a completed third stay during the Promotional Period. Bonus Points earned on Base Points do not count toward Elite tier qualification. Please allow six to eight weeks from completion of any stay for points to appear in you HHonors account. Offer is not transferable and cannot be combined with other select offers.