I fnd it fun to look at Architecture, as when it comes to building web applications you do not want to re invent the wheel every time. before recently there where not many designs for using .Net in a n-tier approach which did not contain DataSets. If you are like me and come from a OO back ground you may see DataSets to be DataCentric and not easy to apply domain rules to the data (neatly).
With the Alt.Net movement promoting a clean OO approch there has been a nice shift from the DataSet designs to Domain Driven technques. The first publised example framework was Patterns in Action. This is quite nice in the sence it promotes the Gang of Four patterns along with some of Martin Fowlers Pattern of Enterprise Application Architecture (PEAA, one of my faviourte books). I have the .Net 2.0 copy (there is a .Net 3.5 one now), which i would reconmned just so you can see how things fit together.
However, there has been another Architecture I have been following, its S#arp Architecture. This is where all my friends woudl know go, "he mentioning it again", at the same time they will think "but he is right this is worth a look". the SA has just released its version 1 RTM release, of which im partictually found of the WCF addition. If you have not been keeping an eye on this I would reconmend downloading the RC2 (just for the word document) and the RTM (for the updated code). I found this Architcture to be extremely impressive. Its easy to understand and its easer to extend. The best thing is the price tag (its FREE).
Before you consider looking at an architecture in .Net I would highly reconmend reading the Foundations of Programming, then looking at S#arp Architecture. you will note between these 2 you will have knowlegde of some extremely good tools and patterns.
thats it for my rant,,, go look at the new S#arp Arhicture now!