Magento : Force Display Mode List/Grid to Specific Categories

this is one coolest magento trick i ever found 😀

you can set on Catalog->Manage Categories, select a category, go to tab Custom Design, then enter following XML on Custom Layout Update field

<reference name="product_list_toolbar">
    <action method="setData"><key>_current_grid_mode</key><value>list</value></action>
</reference>

cheers!