You can try jsreport. It’s free, open sourced, has .net client, cross platform (nodejs), does not require any compilation and it’s safe to let your users to modify their reports. Reports are designed using javascript templating engines that should give you maximum flexibility for your report layout.
CONS
- does not currently support excel and word
- in preview
- does not talk directly with sql db, but you should anyway send data from your BL unless
you are searching for BI reporting
You can try it without any authentication in jsreport playground
