The best Valentines are personal, especially if you are a Special Snowflake whose descendants will honor you in perpetuity. To this end, you can leave offspring born and unborn your DNA, preserved at room temperature for all time in the DNA Time Capsule:
This is the patented, triple-sealed time capsule that securely stores your genetic fingerprint for use by future generations. Preserving one's DNA in the present enables future scientific advances to reveal any predispositions to disease—currently undetectable by today's methods—a family's genetic makeup may bear. Dispensing with the need for long-term refrigerated storage in a lab, a chemical matrix of dissolvable compounds stabilizes DNA within a blood sample at room temperature (blood provides a higher quality and quantity of DNA than samples taken from cheek swabs), preserving the sample for over 100 years. A blood sample can be taken at your preferred medical facility or using the included kit. Once a sample is secured within the capsule, it can be stored within a home or bank lock box for decades until one's progeny submits it for genetic analysis.
Yup, for just under $300 you can leave your genetic code behind for at least a century! Now I am unclear on why your descendants would want to test your DNA rather than just doing their own ("Look Grandpa could have developed dementia if he hadn't been hit by that train!"). Maybe researchers might want to pinpoint when a mutation occurred in a kindred, but that would be for research not any practical benefit (that I can see) to your future relatives.
Maybe I am missing something that the good folks at Hammacher Schlemmer thought about, but I seriously doubt it. They just have a gizmo to sell, and they hope someone with $300 to spare will buy it.
Personally, I would rather have a giftcard for shoes.
Happy Valentines Day anyway!