Question
Smart Catalog offers great features for design intensive catalogs, brochures etc. With Smart Catalog you have full freedom of design and pieces of the content (prices, product, descriptions, images) can be linked to your data (text, XML, ODBC database). Doing translations, or customized pricing is as easy as relinking to another datasource.
At first glance you could think that Smart Catalog is less capable in handling more repetitive catalogs, for example a catalog that lists a lot of products with a consistent page design. However Smart Catalog can be of great help here too. Below we describe various options how to do this with Smart Catalog.

Answer
Note: at the right side you can download the sample files as discussed below.
We assume for this example that we need to create a product catalog that has X products per page and repeats page after page. Note that more variation in design is possible as well.
In order to have a flexible template we will use a sequence ID which can be different from the product SKU. The template will have placeholders linked with Smart Catalog fields to the data using this sequence ID. This way you can make a product selection from your database and load that SKU independent into the template document.
Sample1.indd shows this approach in a 2 page format, but obviously you can add as many pages as you want. The pages can vary in design, might be split up in multiple sections using different master pages etc. If you look inside Sample1.indd you see bunch of elements to make up a product presentation and per presentation each of the fields link to the same sequence ID which in this example just start with 1 and increment. The first page has 3 products, with the third product in a separate design, the second page has 6 products in a standard grid design. After this you could easily have 100s more pages either like page 2 or any different setup.
If we look at our datasource file data.txt we see a list of products that have a sequence ID besides there SKU and the other fields. Linking to this data source (via the Smart Catalog palette menu) and choosing update document will populate the complete document in one go.

The drawback of this approach is that you first need to layout the longest possible document with all elements linked to unique sequence ID's. Per product presentation several links will be used in practice, which means for large documents there is quite some setup time. There are 2 ways to ease this.

Smart Layout offers product presentation functionality giving you one container page item that is linked with a specific ID and all items contained inside the container use this same ID as well. After creation of a product presentation using Smart Layout you can easily duplicate them and with one click they can be assigned to another ID, instead of having to go through all fields one by one.
Creation of a production presentation is done using the Smart Layout tool on the toolbar in combination with the regular InDesign tools. First of all the Smart Layout tool is used to create the presentation are that can be linked with the Smart Catalog palette. Next the Smart Layout tool can be used to create any text box inside the Smart Layout area, graphic frames can be created using the regular tools. Next just the fields have to be selected and that's it.
Note that Smart Layout is a page item of its own which means it can have it's own stroke, fill, drop shadow etc, also very useful. Smart Layout can also act as a text frame itself although for catalogs that is rarely used, To illustrate the usage of Smart Layout open the Sample2 InDesign document and library (the library can only be used with the CS version and not with the CS2 version). Link to the data.txt file and update the document, to see a similar result as sample1. However the setup is quite different because of the usage of Smart Layout. To understand the ease of Smart Layout, drag one of the items from the library and with the Smart Catalog palette assign an ID to see that in one go that complete presentation is field with data for that product.
Smart Layout is both beneficial for manual design to work with building blocks, but also saves a lot of time with the creation of the template as explained in sample1.
Although usage of Smart Layout makes life much easier and saves a lot of time, it still would require manually tagging each production presentation in the template once. Having a 100+ catalog with 10+ products per pages, this means a lot of clicks.

To automate the template creation, ID assignments, you can use the Robot add-on module. The sample script Duplicate Page.js duplicates the last page and updates the assigned SCat IDs (assumed to be integers). To run this script, copy the file Duplicate Page.js to the inDesign/Presets/Scripts folder, show the Scripts palette and double click on the script. Note that the script is written for demo purposes, without any error checking and such. Smart Catalog Robot also supports AppleScript on Mac and VisualBasic on Windows.