Rest in peace. Plans for an alternate engine to the F-35 Joint Strike Fighter jet, which first flew in December of 2006, were imperiled yesterday, a victim of budget cuts in the House. Technology is expensive, and often lives and dies by government funding. Here is a slideshow to help us remember the departed and the declining, the often exciting, occasionally absurd, and always expensive technologies that have lost their support from the U.S. government, and have gone off to the great scrapyard in the sky.

The sky, indeed, is where many of these technologies aspired to be in the first place. Take the alternate engine for the F-35, a radar-evading stealth fighter made by Lockheed Martin. Both the Bush and Obama administrations had struggled for years to kill the alternate engine for the jet, and if the Senate follows suit, the move looks to save the U.S. $3.5 billion over the next few years (leaving us, though, at the whims of a monopoly from Pratt & Whitney, makers of the current engine). When the House finally nudged the engine towards its demise yesterday, it was taken as a sign that Republicans would be willing to accept cuts to the defense budget after all. The House voted 233 to 198 to cancel the jet engine; 47 of those votes were Republican.

Sometimes, though, technologies die even when the money is there to sustain them. The federal government was willing to offer Florida $2.4 billion to fund an experiment in high-speed rail between Tampa and Orlando. Obama had hoped the experiment there could serve as a model for the rest of the nation, but Governor Rick Scott yesterday rejected the plan, becoming the fourth Republican governor to recently kill a major rail project (New Jersey, Ohio, and Wisconsin's governors were the other bullet train skeptics).

Energy technology has not been spared the government's scalpel. The EPA's clean diesel program was very popular and enjoyed bipartisan support. Nonetheless, President Obama has proposed to cut off funding to the program, which helped retrofit school buses to use greener fuel, reported NPR yesterday.

Sometimes it's a technology's time to die. Though Obama's budget slashed some funding for green energy, it also asks for reduced subsidies for the traditional oil and gas giants. It wants to reduce those subsidies by $3.6 billion, in fact. Here's to hoping more coal-fired power plants will join the tech graveyard soon, replaced by cleaner energy.

Back in October, funding cuts to NASA spelled the end of its Constellation Program, which was to further explore the moon. The Ares 1, the rocket shown here, was one of the casualties. There's a glimmer of hope here, however; a few days ago, it was reported that the aviation firms ATK and Astrium would be joining forces to build a cheaper, commercial version of Ares 1 called Liberty.

But it's not just extremely high-tech aviation projects that have been suffering, of late. Over the past few years, police departments have increasingly been grounding their aviation units, making the police helicopter one of the latest technological casualties of budget cuts. In late 2009, Denver grounded its unit, following the example set by units in California, Oklahoma, and elsewhere. It reassigned pilots to patrol duty, and put up its vintage Bell choppers for sale.

Sometimes there is an afterlife for technology killed by the U.S. government. At yesterday's Wired for Change conference at the Ford Foundation in Manhattan, President Bill Clinton recalled how painful it was to lose funding for the Superconducting Super Collider, a particle accelerator built in Texas. Though Clinton issued a plea to Congress, saying "abandoning the SSC at this point would signal that the United States is compromising its position of leadership in basic science," ultimately the funds didn't come through. The SSC effectively lived on, though, in the Large Hadron Collider later built in Switzerland that made headlines last year.

The flight path not taken. The U.S. Army supported the development of a jet pack in the early 1960s, then lost interest when a little situation in Vietnam began to attract its attention and resources. Jet packs were first envisioned in science fiction of the early 20th century. That these aren't the standard means of transportation now is, frankly, disappointing. Perhaps the U.S. government will see the error of its ways soon, funding jetpacks along with other, more deeply lamented, technologies. Until then, there's always the private sector.