This week’s Ask a VC was with Bijan Sabet of Spark Capital, a standout in the younger generation of VCs whether you are looking at his portfolio (Twitter, Tumbr, Boxee, SendMe) or talking to entrepreneurs who work with him.

I asked Sabet about how fundraising went for Spark Capital, which just raised its third fund, and how much that early investment in Twitter helped the process. We also talk about a running theme on this show– how startups outside the US can get US VC attention, and the limited investments that Spark has done overseas. We talk about basic ways in which Spark– and Sabet in particular– like to be pitched, the slide that will turn him off immediately and whether he ever funds one-man startups.

We have an interesting chat about the travel space and the degree to which the big opportunity is in smaller, fragmented offerings. (Part three hundred in my series on why existing travel incumbents do not work for anything other than flights and car rentals.) We even talk about the roles that non-travel sites like Foursquare or Hunch could play in solving these greater problems.

And we close with a really interesting discussion about the state of Web investing in Boston, where most of the Spark partners live but where they do very few deals. In an age when you can start a Web business anywhere, why can’t this former hub of venture capital– still flush with universities, talent and cash– get its mojo going? Sabet tells us what he’s trying to do about it.