The Y2K-related glitches we've seen so far have ranged from the silly to the scary. In Maine, an inconvenient yet innocuous glitch registered automobiles as horse-less carriages. But in California, a Y2K-test-gone-awry spewed sewage into the streets. Still, counties, cities and companies in the US are learning from the snafus, and vow to at least ensure health and safety, even if they can't thwart minor annoyances. "In this country, we're very optimistic that it's going to be along the lines of inconveniences rather that tragedy," said Don Meyer, spokesman for the US Senate's Y2K committee. However, he acknowledged that even the experts don't really know what's going to happen after the clock strikes midnight at the end of this month. "The minor inconveniences we've seen may be a harbinger of things to come," Meyer conceded. "Of course, we hope that's not the case." The glitch, as most folks know by now, occurs when computers read the date 2000 as 1900, because of software designed to read only the last two years in a date. The first major manifestation of the glitch occurred a few years ago, when computers started rejecting purchases from people using credit cards that expired in 2000. Others lost their ATM cards, after cash machines gobbled them up because the 2000 expiration date just wouldn't compute. Banks moved swiftly to address the problem, and have become leaders in addressing Y2K fears. But after the debacle, many delayed issuing cards with 2000 expiration dates for several months while they tackled the glitch. Since then, other date-related problems have surfaced as companies and government agencies have tested their software to make sure it's Y2K compliant -- only to find in some cases that it was not. In June, one of the largest Y2K tests spawned a potential health hazard, as four million gallons of raw sewage spewed onto Southern California streets. During testing at local reclamation plan, a computer shut a gate by mistake, backing up sewage into the city of Van Nuys. City officials now say the problem has been resolved. Others are hoping that the medical community has addressed the glitches it has seen so far. Tufts Medical plan dropped 18,000 Medicaid patients earlier this year, after it decided fixing Y2K glitches took precedence over keeping up the Medicaid system. The city of San Jose, California, found a glitch in the defibrillators in its ambulances, and sent them into the manufacturer to be repaired. Glitches also have plagued businesses. At least one food distributor lost a large amount of inventory before it discovered its computer system was tossing out items that expired in 2000, thinking they had sat on the shelf for the past 99 years. Other incidents, such as the horse-less carriage snafu in Maine, have been almost laughable. In Philadelphia, about 500 people got a jury summons in November telling them to show up in 1900. And the Social Security Administration alarmed 30,000 people earlier this year by sending them notices that their benefits would expire in 1900. The biggest worry among some tech experts is the virus explosion that could come as malicious hackers take advantage of people's Y2K fears. So far, researchers have found at least seven Y2K-related viruses, including some that masquerade as a Y2K fix and others that could harm computers when the New Year strikes. The White House was so concerned about New Year's viruses and hacks it appealed to hackers and virus writers not to pick New Year's weekend for exploits. But even on the virus front, it hasn't been as bad as experts expected. "There's been very little activity," said Carey Nachenberg, Chief Researcher at Symantec's AntiVirus Research Centre. "People have been very calm." Take me to the Year 2000 Special.