A quick geek intermission:

Liquid supports the elsif construct now.

{% if cart.total_weight > 5000 %} 
  ... estimating {{ 2000 | money_with_currency }} in shipping ...
{% elsif cart.total_weight > 2500 %} 
  ... estimating {{ 1000 | money_with_currency }} in shipping ...
{% elsif cart.total_weight > 1000 %} 
  ... estimating {{ 500 | money_with_currency }} in shipping ...
{% else %} 
  ... estimating free shipping ...
{% endif %} 

Normal program resumes immediately