When to user Abstract Class vs Interface

The following links provide a good overview of when to use Abstract Classes vs Interfaces.

http://objectspot.blogspot.com/2006/07/abstarct-class-vs-interface.html

and

http://www.codeproject.com/KB/architecture/Abstract_Interface.aspx

Send email to multiple users in Designer workflow

To send email to multiple users in Designer workflow using a Person or Group column.

Refer the links below.

http://rapidapplicationdevelopment.blogspot.com/2007/04/multi-value-columns-in-sharepoint.html

and

http://social.msdn.microsoft.com/forums/en-US/sharepointworkflow/thread/ebcb81ec-ba36-4a4c-bd01-26dc2c4d0913

Redirect from a Page(Document Library) to any custom location in MOSS 2007

Hi,
There was a requirement to redirect a user when (s)he clicks on a Document Library link from Quick Launch to a Shared Network Location, where the actual documents would reside. This was achieved in the following way.
Go to Site Actions ->Edit Page(of the document library in this case). Click Add a Web Part. In the Dialog Box that appears, pick Content Editor Web Part and click Ok. Click on Open the tool pane and click on the Source Editor button, add the following code to the Source Editor window.
<meta equiv="refresh" content="10;url=\\shared location">
where 10 is the number of seconds, after which the refresh occurs.
This was referred from the following link.
http://www.toddklindt.com/blog/Lists/Posts/Post.aspx?ID=48

Connected Web Parts in MOSS

Check out this nice link for Developing Connected Web parts.
http://www.codeproject.com/KB/sharepoint/ConnectingCustomWebParts.aspx

Currency to Decimal Conversion in .Net

Check out the nice link below to Convert Currency back to Decimal.

http://geekswithblogs.net/marocanu2001/archive/2008/02/05/convert-currency-string-back-to-decimal.aspx

WorkFlow Dev Link MSDN

Nice link for Developing Workflows in Sharepoint using Visual Studio 2008
http://msdn.microsoft.com/en-us/library/cc936631.aspx

Good Link for MVC Pattern

http://msdn.microsoft.com/en-us/library/ms978748.aspx