Mashups, which unite disparate data sources in quickly developed Web applications, are a hot topic at the Web 2.0 Expo conference in San Francisco this week, with companies including Serena Software, JackBe, and Kapow Technologies offering new products geared to mashup development.

Offerings include an online marketplace and a hosted service for mashups.

Serena is launching Tuesday its Serena Mashup Exchange, an online marketplace for marketing "Business Mashups." Serena defines Business Mashups as mashups that solve business problems and combine visual and data elements from multiple sources within a process-driven framework.

Business users, IT departments, and others can find, buy and sell pre-packaged mashups, Web services and professional services without incurring fees or commissions from Serena. The company said it is providing the marketplace in an effort to control the "long tail" of IT applications, which are projects that individually are too small to warrant IT support yet represent a market opportunity.

With Mashup Exchange, companies can build "MicroExchanges" for secure internal interchange between IT and business units, such as publishing mashup-enabled access to an internal SAP system.

Additionally, Serena and CapGemini said they are helping companies bring Web-based consumer-oriented technology into the enterprise via CapGemini's RAIN (Rapid Innovation) environment for developing business models for a service-oriented enterprise. With RAIN, workers can address business issues on their own rather than relying on IT. RAIN enables professionals to compose a mashup without the need for programming skills. Serena's Business Mashup tools can be leveraged in the process.

JackBe is announcing Tuesday general availability of Presto 2.0, the second generation of its enterprise mashup platform. Featured are enterprise mashup widgets called "Mashlets," which are portable, shareable micro Web applications used for common knowledge worker activities such as analyzing sales data and enterprise risk analysis. Users can share Mashlets through enterprise portals, blogs, wikis, or e-mail.

Also featured in Presto 2.0 is connectivity for products like Excel, HP SOA Systinet, and Adobe Flash/Flex. A mashup development plugin for the Eclipse platform has been built as well.

"Enterprise technology is encountering a ‘perfect storm’ of SOA, mashups, and widgets that are converging to finally allow the business to address their most dynamic information needs. And enterprise mashup platforms like Presto 2.0 are an integral part of that solution" said John Crupi, CTO at JackBe, in a statement released by the company. "Presto 2.0 greatly expands the speed, scale, and scope of information use and re-use within the enterprise. Presto Mashlets alone make Presto 2.0 worth looking at, but we went much further, bringing mashups and mashlets to every major tool in use by business user and developers."

Presto Wires, a visual mashup development tool, is featured in version 2.0 along with Presto Connector for Excel, for consuming mashups in Excel and publishing mashup-ready Excel spreadsheets.

Kapow Technologies will show off Kapow OnDemand on Tuesday, providing a hosted service for building enterprise mashup applications that provide structured "Web intelligence," the company said.

Based on the Kapow Mashup Server, Kapow OnDemand offers access to underlying data sources and services to be mashed. Users also can import Web data into existing applications and IT infrastructure via XML.

OnDemand features a "Robot Designer" to construct custom Web harvesting feeds and services in a role-based execution runtime, the company said. Monitoring and management tools also are featured.

Deployed on a commercial-grade grid, OnDemand provides a secure service featuring load balancing, high availability, failover, and automated backup and restore, Kapow said.

Users can access a visual scripting environment for building services and feeds that automate collection and delivery of Web intelligence.

Pricing for Kapow OnDemand is based on a subscription with prices starting at $3,400 per month.

Kapow also is announcing Kapow Connector for Excel, enabling Excel spreadsheet users to use Web services that provide data directly to their spreadsheet. The connector is used in combination with Kapow OnDemand or Kapow Mashup Server Web 2.0 edition. Users can analyze Web intelligence on their desktop.