Top 20 NuGet .net Packages

MVVM Helpers is a library of classes for WPF, WinRT, WinPRT, Xamarin.iOS and Xamarin.Android to implement the MVVM design pattern. It also includes several Blend behaviors, attached behaviors, extension methods and general .NET classes to aid in the development of .NET applications.
Friendly asynchronous calls for all .Net versions, free and open-source library
PortableExtensions is a set of .Net extension methods build as portable class library. PortableExtensions enhance the .Net framework by adding a bunch of methods to increase developer’s productivity.
A library of abstractions for the purpose of testing. It is named after the author who wrote the book of James in the Bible. (James 1:2-3)
NFaker is a rewrite of ruby ffaker to .net Developers
Finaquant Protos is a non-commercial and free .NET library with table-valued functions (Table Functions). This .NET library can only be used for non-commercial purposes like education and science. Please see Finaquant Calcs with additional features and unlimited table size for commercial use.
Dark Notes is a library that uses the Java Native Interface (JNI) to load the Java VM into a .NET process on Windows, and exposes the Java classes and methods in an easy-to-call way using the .NET Dynamic Language Runtime (DLR).
An application framework that makes you very fluent in developing .NET applications
FileDb is a free to use simple NoSQL database Portable Class Library for .NET - Stores one table per file, including its index - Extremely small size DLL - Supports field types Int, UInt, Bool, String, Byte, Float, Double and DateTime and also arrays of the same types - Index supports a single Prim...
Wddx.Net is a WDDX serializer/deserializer for .NET.
Rubor is a Class library C# with many Ruby features! Our Extensions mirror ruby methods. For example, Rubor improve the Array C# with methods like "map", "join" etc!
Simple Guard for .NET http://damienbod.wordpress.com/2014/08/29/policeman-guard-nuget-package/
Eloquent is a small collection of fluent (or fluent-like) expressions for .NET
String operations/validation functions
Nemiro.Convertion is small helper class for converting a data types to another data types in .NET Framework. Features * Safe conversion the DBNull, NULL and empty values; * Processing floating-point numbers, regardless of the type of decimal separator (dot or comma); * Number system conversion: ...
Gnostice PDFOne .NET is a versatile PDF component suite for .NET developers to implement PDF-related tasks in their applications. PDFOne .NET can create, edit, view, print, search, redact, encrypt, decrypt, digitally sign, merge, split, reorganize, bookmark, annotate, watermark, and stamp PDF docume...