As European flights resumed Wednesday after a week-long shutdown because of ash from the Icelandic volcano, the ripple effects have been felt all over the world, including at Yale.

Professors, conference-bound students and even some prefrosh headed for Bulldog Days found themselves stranded. But out of the ashes, another group of students found an entrepreneurial opportunity.

Linguistics professor Stephen Anderson has been in Amsterdam for the past week, originally traveling to Utrecht to attend a major international conference on the evolution of language. His flight back to Yale was cancelled on Sunday.

“I do realize that some people actually come to Amsterdam for a week of their own volition and it’s not exactly hardship duty,” he said in an e-mail, “but I have no particular interest in being here now and there are things I need to be doing back in New Haven.”

Professor Ludger Viefhues-Bailey, who was presenting a paper at the University of Lucern, came up with solution to the transatlantic divide: Web-based video conferencing in order to resume his lectures. He said he hopes to fly back today.

“With the help of this tool my students could share their PowerPoint presentations both with me in Switzerland and the class in New Haven,” he said in an e-mail. “I could discuss with them their presentations and the upcoming final paper.”

Meanwhile, archaeology professor Harvey Weiss, has been stuck in London after attending an archaeology conference for more than eight days now. His first concern, he said, was for his students, but in the days following his mind has centered on the question of, “Who is going to pay for my hotel?”

Three of Weiss’s students said they are celebrating a short-lived break from classes, but all the while knowing the break is indeed temporary.

“I’m not looking forward to having to make up these classes over reading week,” said Matthew Miller ’12, a student in Weiss’s “Genesis and Collapse of Old World Civilizations” lecture.

Also in London, a student network of 300 entrepreneurs under age 30 (including 15 Yale students and graduates) called Sandbox organized a conference for the stranded internationals in London. One of the organizers, Nathaniel Whittemore, was en route from the Skoll World Forum on Social Entrepreneurship at Oxford University when he realized that all of his fellow conference speakers were also stuck at the airport. In less than 36 hours, they organized a conference, featuring speakers such as eBay founder Jeff Skoll and drawing more than 150 attendees, and broadcast it over the Internet. The program received 3,000 hits in real time and another 9,000 in the few days thereafter.

“For us, it was impressive to see how a network can move things in a really short amount of time,” said Fabian Pfortmüller, a co-founder of Sandbox, and a Columbia student who helped organize the conference.

Sandbox co-founder Christian Busch, a student at the London School of Economics, said the unforeseen concentration of world leaders in London allowed for the innovative event.

Old-fashioned, in-person conferences were also affected, such as Unite for Sight Global Health Conference at Yale this past weekend, which saw fewer speakers and students than expected, said Hari Iyer, a conference attendee from Olin College. Nevertheless, Andriy Maksymovch from Ukraine, who was supposed to present his project at the conference this past weekend but ended up stranded in London, kept his situation in perspective.

“There was nothing else I could do in those circumstances,” he said in an e-mail. “I am sure that every one of thousands of people who were stuck in the airports had their own important plans —family reunions, marriages, funerals — that were disrupted by the events in Iceland.

Correction: April 23, 2010

An earlier version of this article misspelled the name and misstated the gender of Professor Ludger Viefhues-Bailey. The News sincerely regrets the error.