That instant relic known as the Rail Runner Express continues to enjoy popularity among New Mexicans and visitors even as its governing Rio Metro Transit Board boosts weekday fares by a dollar and reduces — but doesn't eliminate — Saturday service.

While the fare increase is tied to federal regulations and supposedly not to the passenger line's quarter-million-dollar operating shortfall, the transit board clearly is squeezed for revenue. That's likely to be a long-standing challenge, and the more creative thinking the Rail Runner can gather, the better. One such thought, from a regular passenger: Put Santa Fe police, car-privileged state employees and other public servants commuting from the Albuquerque area on the train instead of making them part of the one-to-a-car crowd cramming I-25.

Many other suggestions are sure to arise as the trains drain money — but they're worth taxpayer subsidies on economic, public-safety and environmental grounds. And, of course, highways, ports, airports and other transportation already are subsidized.

The greatest ongoing challenge to the trains is the time it takes 'em to get from the Duke City to the capital: An hour and a half, más o menos, all too often mas más que menos, and the more stations that pop up along the route, the longer it'll take. How attractive is the train ride, for all its comfort and the efficiency of folks getting work done while aboard, when passengers see cars overtake them on the way to their very destination — as opposed to catching a shuttle bus at the train stop?

What raises the velocity issue once again is President Barack Obama's announcement of $8 billion worth of economic-recovery funds for high-speed rail: He began with $1.25 billion for such a train line connecting Orlando to Tampa, Fla. — at a comparatively poky 120 mph, but more than $2 billion worth of the federal money would help start a project that would lead to 2 1/2-hour trips from Los Angeles to San Francisco; an effort for which notoriously bond-wary Californians have approved an issue.

Obama is offering little to the Boston-to-Washington corridor — just over $100 million — perhaps because Amtrak's Acela already zips between those cities. But for all its 100-mph-plus capabilities, its average speed is only about 80; this at a time when in Japan, France, even Italy, trains regularly exceed 200 mph.

To lighten inter-city traffic and contribute at least something to safety and, perhaps, reduce exhaust emissions, the president's job-boosting push for faster trains is long overdue.

A speedier Acela should have been part of the consideration — and the day will come when the Rail Runner, excellent beginning that it is, must offer its commuting customers faster trips.

We hope the initiatives being taken along higher-population corridors will, in years to come, dribble down to the Río Grande Corridor — then up to Taos, and, by one route or another, on to Cheyenne and down to El Paso ...