How to have an irregular grid - 2 different image sizes

[Paldru]

I am trying to change the style of how my products appear on the product list. I would like to have two different image sizes each on its own row. First row has 5 products (classic grid style) but the second row would have only one product with a much bigger thumbnail. The third row again would have the five smaller product thumbs and so forth. Could this be done through only the template?

[NemoPS]

Well you might be able to achieve it by having the image size as the bigger one you need, then use css to hardcode dimensions, like by using the :nth-child selector to target even/odd rows